Note 1 – Summary of Significant Accounting Policies and Nature of Operations

U.S. Auto Parts Network, Inc. (including its subsidiaries) is a distributor of aftermarket auto parts and accessories and was established in 1995. The Company entered the e-commerce sector by launching its first website in 2000 and currently derives the majority of its revenues from online sales channels. The Company sells its products to individual consumers through a network of websites and online marketplaces. Our flagship websites are located at www.autopartswarehouse.com, www.partstrain.com, www.jcwhitney.com, www.stylintrucks.com, www.AutoMD.com and our corporate website is located at www.usautoparts.net. References to the “Company,” “we,” “us,” or “our” refer to U.S. Auto Parts Network, Inc. and its consolidated subsidiaries.

The Company’s products consist of body parts, engine parts, performance parts and accessories. The body parts category is primarily comprised of parts for the exterior of an automobile. Our parts in this category are typically replacement parts for original body parts that have been damaged as a result of a collision or through general wear and tear. The majority of these products are sold through our websites. In addition, we sell an extensive line of mirror products, including our own private-label brand called Kool-Vue™, which are marketed and sold as aftermarket replacement parts and as upgrades to existing parts. The engine parts category is comprised of engine components and other mechanical and electrical parts, which are often referred to as hard parts. These parts serve as replacement parts for existing engine parts and are generally used by professionals and do-it-yourselfers for engine and mechanical maintenance and repair. We offer performance versions of many parts sold in each of the above categories. Performance parts and accessories generally consist of parts that enhance the performance of the automobile, upgrade existing functionality of a specific part or improve the physical appearance or comfort of the automobile.

The Company is a Delaware C corporation and is headquartered in Carson, California. The Company also has employees located in Kansas, Virginia, Illinois and Ohio, as well as in the Philippines.

Basis of Presentation

The consolidated financial statements of the Company have been prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) for interim financial information and with the instructions to U.S. Securities and Exchange Commission (“SEC”) Form 10-Q and Article 10 of SEC Regulation S-X. In the opinion of management, the accompanying consolidated financial statements contain all adjustments, consisting of normal recurring adjustments, necessary to present fairly the consolidated financial position of the Company as of September 29, 2012 and the consolidated results of operations for the thirteen and thirty-nine weeks ended September 29, 2012 and October 1, 2011, and cash flows for the thirty-nine weeks ended September 29, 2012 and October 1, 2011. Certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to the rules and regulations of the SEC. The Company’s results of operations for the thirty-nine weeks ended September 29, 2012 are not necessarily indicative of those to be expected for the entire fiscal year. The accompanying consolidated financial statements should be read in conjunction with the Company’s Annual Report on Form 10-K for the year ended December 31, 2011, which was filed with the SEC on March 26, 2012.

Fiscal Periods

The Company’s fiscal year is based on a 52/53 week fiscal year ending on the Saturday closest to December 31. Quarterly periods are based on the thirteen weeks ending on the Saturday closest to the calendar quarter end date.

Principles of Consolidation

The consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. Intercompany balances and transactions have been eliminated.

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Significant estimates made by management include, but are not limited to, those related to revenue recognition, uncollectible receivables, the valuation of investments, valuation of inventory, valuation of deferred tax assets and liabilities, valuation of intangible assets including goodwill and other long-lived assets, recoverability of software development costs, contingencies and share-based compensation expense that results from estimated grant date fair values and vesting of issued equity awards. Actual results could differ from these estimates.

Statement of Cash Flows

The net change in the Company’s book overdraft is presented as an operating activity in the consolidated statement of cash flows. The book overdraft represents a credit balance in the Company’s general ledger but the Company has a positive bank account balance.

Fair Value of Financial Instruments

The carrying values of cash and cash equivalents, accounts receivable and accounts payable approximate fair value at September 29, 2012 and December 31, 2011 due to their short-term maturities. Marketable securities and investments are carried at fair value, as discussed below. Based on the borrowing rates currently available to the Company for bank loans with similar terms and average maturities, the fair value of our revolving loan payable, classified as current liability in our consolidated balance sheets, approximates its carrying amount because the interest rate is variable. If the Company’s revolving loan payable (see “Note 6 – Borrowings”) had been measured at fair value at September 29, 2012, it would be categorized in Level 2 of the fair value hierarchy, as the estimated value would be based on the quoted market prices for the same or similar issues or on the current rates available to the Company for debt of the same or similar terms. Accordingly, financial instruments that are not measured at fair value include accounts receivable, accounts payable and debt. Refer to “Note 3 – Fair Value Measurements” for additional fair value information.

Accounts Receivable and Concentration of Credit Risk

Accounts receivable are stated net of allowance for doubtful accounts. The allowance for doubtful accounts is determined primarily on the basis of past collection experience and general economic conditions. The Company determines terms and conditions for its customers primarily based on the volume purchased by the customer, customer creditworthiness and past transaction history.

Concentrations of credit risk are limited to the customer base to which the Company’s products are sold. The Company does not believe significant concentrations of credit risk exist.

Marketable Securities and Investments

Marketable securities and investments are comprised of closed-end funds primarily invested in mutual funds and auction rate preferred securities (“ARPS”). As of September 29, 2012, the Company’s investments were primarily comprised of closed-end mutual funds. Mutual funds are classified as short-term investments available-for-sale and recorded at fair market value, based on quoted prices of identical assets that are trading in active markets as of the end of the period for which the values are determined. The Company’s ARPS were fully redeemed at par value during the second quarter of 2012 (further described in Note 3 under the caption “Financial Assets Valued on a Recurring Basis”). The underlying investments in ARPS were tax-exempt municipal bonds with maturities of thirty or more years, for which the interest rates are reset through a “Dutch auction” every seven days. In accordance with Accounting Standards Codification (“ASC”) Topic 320 Investments – Debt and Equity Securities and based on the Company’s ability to market and sell these instruments, the Company classified its ARPS as available-for-sale and carried them at fair value.

Other-Than-Temporary Impairment

All of the Company’s marketable securities and investments are subject to a periodic impairment review. The Company recognizes an impairment charge when a decline in the fair value of its investments below the cost basis is judged to be other-than-temporary. The Company considers various factors in determining whether to recognize an impairment charge, including the length of time and extent to which the fair value has been less than the Company’s cost basis, the financial condition and near-term prospects of the investee, and the Company’s intent and ability to hold the investment for a period of time sufficient to allow for any anticipated recovery in the market value. No other-than-temporary impairment charges were recorded on any investments during the thirty-nine week periods ended September 29, 2012 and October 1, 2011.

Inventory

Inventories consist of finished goods available-for-sale and are stated at the lower of cost or market value, determined using the first-in first-out method. The Company purchases inventory from suppliers both domestically and internationally, and routinely enters into supply agreements with U.S. based suppliers and its primary drop-ship vendors. The Company believes that its products are generally available from more than one supplier and seeks to maintain multiple sources for its products, both internationally and domestically. The Company primarily purchases products in bulk quantities to take advantage of quantity discounts and to ensure inventory availability. Inventory is reported at the lower of cost or market, adjusted for slow moving, obsolete or scrap product. Inventory at September 29, 2012 and December 31, 2011 was $48.7 million and $52.2 million, respectively, which included items in-transit to our warehouses, in the amount of $3.3 million and $9.6 million, respectively.

Website and Software Development Costs

The Company capitalizes certain costs associated with website and software developed for internal use according to ASC 350-50 Intangibles – Goodwill and Other – Website Development Costs and ASC 350-40 Intangibles – Goodwill and Other – Internal-Use Software, when both the preliminary project design and testing stage are completed and management has authorized further funding for the project, which it deems probable of completion and to be used for the function intended. Capitalized costs include amounts directly related to website and software development such as payroll and payroll-related costs for employees who are directly associated with, and who devote time to, the internal-use software project. Capitalization of such costs ceases when the project is substantially complete and ready for its intended use. These amounts are amortized on a straight-line basis over two to three years once the software is placed into service.

Long-Lived Assets and Intangibles

The Company accounts for the impairment and disposition of long-lived assets, including intangibles subject to amortization, in accordance with ASC 360 Property, Plant and Equipment (“ASC 360”). Management assesses potential impairments whenever events or changes in circumstances indicate that the carrying value of an asset may not be recoverable. An impairment loss will result when the carrying value exceeds the undiscounted cash flows estimated to result from the use and eventual disposition of the asset. Impairment losses will be recognized in operating results to the extent that the carrying value exceeds the discounted future cash flows estimated to result from the use and eventual disposition of the asset. The Company continually uses judgment when applying these impairment rules to determine the timing of the impairment tests, undiscounted cash flows used to assess impairments, and the fair value of a potentially impaired asset. The reasonableness of our judgments could significantly affect the carrying value of our long-lived assets. The Company did not recognize any impairment losses on long-lived assets and intangibles subject to amortization during the thirty-nine weeks ended September 29, 2012 and October 1, 2011.

Goodwill and Indefinite-Lived Intangibles

The Company accounts for goodwill and indefinite-lived intangible assets in accordance with ASC 350 Intangibles – Goodwill and Other (“ASC 350”). Under ASC 350, goodwill and intangible assets with indefinite lives are not amortized but are tested for impairment annually or more frequently if events or circumstances occur that would indicate a reduction in fair value. In addition, the Company identified a single reporting unit (refer to “Segment Data” below) in accordance with ASC 280 Segment Reporting. The Company’s annual testing date is October 31. The goodwill impairment test is a two-step impairment test. The first step compares the fair value of each reporting unit with its carrying amount including goodwill. If the carrying amount exceeds the estimated fair value, then the second step of the impairment test is performed to measure the amount of any impairment loss. Impairment losses will be recognized in operating results. ASC 350 also provides the option to first assess qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more likely than not that the fair value of a reporting unit is less than its carrying amount. If, after assessing the totality of events or circumstances, an entity determines it is not more likely than not that the fair value of a reporting unit is less than its carrying amount, then performing the two-step impairment test is unnecessary. During the thirty-nine weeks ended September 29, 2012 and October 1, 2011, there were no events or circumstances that indicated a possible reduction in the Company’s goodwill and indefinite-lived intangible asset fair values, accordingly, no such impairment loss was recognized for periods then ended.

Revenue Recognition

The Company recognizes revenue from product sales when the following four revenue recognition criteria are met: persuasive evidence of an arrangement exists, delivery has occurred, the selling price is fixed or determinable, and collectability is reasonably assured. The Company retains the risk of loss or damage during transit, therefore, revenue from product sales is recognized at the delivery date to customer, not upon shipment.

Revenue from sales of advertising is recorded when performance requirements of the related advertising program agreement are met.

The Company evaluates the criteria of ASC 605-45 Revenue Recognition Principal Agent Considerations in determining whether it is appropriate to record the gross amount of product sales and related costs or the net amount earned as commissions. Generally, when the Company is the primary party obligated in a transaction, the Company is subject to inventory risk, has latitude in establishing prices and selecting suppliers, or has several but not all of these indicators, revenue is recorded at gross.

Product sales and shipping revenues, net of promotional discounts and return allowances, are recorded when the products are delivered and title passes to customers. Retail items sold to customers are made pursuant to terms and conditions that provide for transfer of both title and risk of loss upon our delivery to the customer. Return allowances, which reduce product revenue by the Company’s best estimate of expected product returns, are estimated using historical experience.

Payments received prior to the delivery of goods to customers are recorded as deferred revenue.

The Company periodically provides incentive offers to its customers to encourage purchases. Such offers include current discount offers, such as percentage discounts off current purchases and other similar offers. Current discount offers, when accepted by the Company’s customers, are treated as a reduction to the purchase price of the related transaction.

Sales discounts are recorded in the period in which the related sale is recognized. Sales return allowances are estimated based on historical amounts and are recorded upon recognizing the related sales. Credits are issued to customers for returned products.

No customer accounted for more than 10% of the Company’s net sales.

Cost of Sales

Cost of sales consists of the direct costs associated with procuring parts from suppliers and delivering products to customers. These costs include direct product costs, outbound freight and shipping costs, warehouse supplies and warranty costs, partially offset by purchase discounts and cooperative advertising. Depreciation and amortization expenses are excluded from cost of sales and included in marketing, general and administrative and fulfillment expenses as noted below.

Warranty Costs

The Company or the vendors supplying its products provide the Company’s customers limited warranties on certain products that range from 30 days to lifetime. In most cases, the Company’s vendors are the party primarily responsible for warranty claims. Standard product warranties sold separately by the Company are recorded as deferred revenue and recognized ratably over the life of the warranty, ranging from one to five years. The Company also offers extended warranties that are imbedded in the price of selected branded products we sell. The product brands that include the extended warranty coverage are offered at three different service levels: (a) a five year unlimited product replacement, (b) a five year one-time product replacement, and (c) a three year one-time product replacement. Warranty costs relating to merchandise sold under warranty not covered by vendors are estimated and recorded as warranty obligations at the time of sale based on each product’s historical return rate and historical warranty cost. During the second quarter of 2012, the Company updated its estimate of warranty obligations which resulted in an adjustment to warranty liabilities of $232,000. The standard and extended warranty obligations are recorded as warranty liabilities, included in other current liabilities in the consolidated balance sheets. For the thirty-nine weeks ended September 29, 2012 and October 1, 2011, the activity in our aggregate warranty liabilities was as follows (in thousands):

Marketing Expense

Marketing costs, including advertising, are expensed as incurred. The majority of marketing expense is paid to internet search engine service providers and internet commerce facilitators. For the thirteen weeks ended September 29, 2012 and October 1, 2011, the Company recognized advertising costs of $5.0 million and $7.0 million, respectively. For the thirty-nine weeks ended September 29, 2012 and October 1, 2011, the Company recognized advertising costs of $16.3 million and $21.6 million, respectively. Marketing expense also includes depreciation and amortization expense and share-based compensation expense.

General and Administrative Expense

General and administrative expense consists primarily of administrative payroll and related expenses, merchant processing fees, legal and professional fees and other administrative costs. General and administrative expense also includes depreciation and amortization expense and share-based compensation expense.

Fulfillment Expense

Fulfillment expense consists primarily of payroll and related costs associated with warehouse employees and the Company’s purchasing group, facilities rent, building maintenance, depreciation and other costs associated with inventory management and wholesale operations. Fulfillment expense also includes share-based compensation expense.

Technology Expense

Technology expense consists primarily of payroll and related expenses of our information technology personnel, the cost of hosting the Company’s servers, communications expenses and Internet connectivity costs, computer support and software development. Technology expense also includes share-based compensation expense.

Share-Based Compensation

The Company accounts for share-based compensation in accordance with ASC 718 Compensation – Stock Compensation (“ASC 718”). All stock options issued to employees are recognized as share-based compensation expense in the financial statements based on their respective grant date fair values, and are recognized within the statement of comprehensive income or loss as marketing, general and administrative, fulfillment or technology expense, based on employee departmental classifications.

Under this standard, the fair value of each share-based payment award is estimated on the date of grant using an option pricing model that meets certain requirements. The Company currently uses the Black-Scholes option pricing model to estimate the fair value of share-based payment awards, with the exception of options granted containing market conditions (none in fiscal years 2012 and 2011), for which the Company estimates the fair value using a Monte Carlo model. The determination of the fair value of share-based payment awards utilizing the Black-Scholes and Monte Carlo models is affected by the Company’s stock price and a number of assumptions, including expected volatility, expected life, risk-free interest rate and expected dividends.

Prior to January 1, 2012, the Company estimated volatility using the historical volatilities of similar public entities. Due to the limited period of time our equity shares have been publicly traded, we did not have sufficient historical market price data to provide a reasonable basis upon which to estimate volatility. As of January 1, 2012, the Company has incorporated its own historical volatility into the grant-date fair value calculations. The Company’s historical volatility was not materially different than the estimates applied to past award fair value calculations. The expected term of an award is based on combining historical exercise data with expected weighted time outstanding. Expected weighted time outstanding is calculated by assuming the settlement of outstanding awards is at the midpoint between the remaining weighted average vesting date and the expiration date. Prior to January 1, 2012, the expected life of an award was estimated using the “simplified” method as provided in ASC 718. Under this method, the expected life equals the arithmetic average of the vesting term and the original contractual term of the award. The Company used the simplified method as it did not have sufficient historical exercise data to provide a reasonable basis upon which to estimate an expected term. The risk-free interest rate assumption is based on observed interest rates appropriate for the expected life of awards. The dividend yield assumption is based on the Company’s expectation of paying no dividends. Forfeitures are estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures significantly differ from those estimates. The Company considers many factors when estimating expected forfeitures, including employee class, economic environment, and historical experience.

The Company accounts for equity instruments issued in exchange for the receipt of services from non-employee directors in accordance with the provisions of ASC 718.

The Company accounts for equity instruments issued in exchange for the receipt of goods or services from other than employees in accordance with ASC 505-50 Equity-Based Payments to Non-Employees. Costs are measured at the estimated fair market value of the consideration received or the estimated fair value of the equity instruments issued, whichever is more reliably measurable. The value of equity instruments issued for consideration other than employee services is determined on the earlier of a performance commitment or completion of performance by the provider of goods or services. Equity instruments awarded to non-employees are periodically re-measured as the underlying awards vest unless the instruments are fully vested, immediately exercisable and non-forfeitable on the date of grant.

Other Income, net

Other income, net consists of miscellaneous income or expense such as gains/losses from disposition of assets, and interest income comprised primarily of interest income on investments.

Interest Expense

Interest expense consists primarily of interest expense on our outstanding loan balance, deferred financing cost amortization, and capital lease interest.

Income Taxes

The Company accounts for income taxes in accordance with ASC 740 Income Taxes (“ASC 740”). Under ASC 740, deferred tax assets and liabilities are recognized for the future tax consequences attributable to temporary differences between the financial statement carrying amount of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. When appropriate, a valuation allowance is established to reduce deferred tax assets, which include tax credits and loss carry forwards, to the amount that is more likely than not to be realized. In making such determination, the Company considers all available positive and negative evidence, including future reversals of existing taxable temporary differences, future taxable income exclusive of reversing temporary differences and carryforwards, taxable income in prior carryback years, tax planning strategies and recent financial operations.

The Company utilizes a two-step approach to recognizing and measuring uncertain tax positions. The first step is to evaluate the tax position for recognition by determining if the weight of available evidence indicates it is more likely than not that the position will be sustained on audit, including resolution of related appeals or litigation processes. The second step is to measure the tax benefit as the largest amount which is more than 50% likely of being realized upon ultimate settlement. The Company considers many factors when evaluating and estimating our tax positions and tax benefits, which may require periodic adjustments and which may not accurately forecast actual outcomes. As of September 29, 2012, the Company had no material unrecognized tax benefits, interest or penalties related to federal and state income tax matters. The Company’s policy is to record interest and penalties as income tax expense.

Foreign Currency Translation

For each of the Company’s foreign subsidiaries, the functional currency is its local currency. Assets and liabilities of foreign operations are translated into U.S. dollars using the current exchange rates, and revenues and expenses are translated into U.S. dollars using average exchange rates. The effects of the foreign currency translation adjustments are included as a component of accumulated other comprehensive income or loss in our consolidated balance sheets.

Comprehensive Income

The Company reports comprehensive income or loss in accordance with ASC 220 Comprehensive Income. Accumulated other comprehensive income or loss, included in our consolidated balance sheets, includes foreign currency translation adjustments related to the Company’s foreign operations, and unrealized holding gains and losses from available-for-sale marketable securities and investments. The Company presents the components of net income or loss and other comprehensive income or loss, in our consolidated statements of comprehensive income or loss.

Segment Data

The Company operates in one reportable segment and reporting revenues by product line or geographic location is impracticable. Certain long-lived assets are held in the Philippines (refer to “Note 4 – Property and Equipment, Net”). The criteria the Company used to identify our reporting segment are primarily the nature of the products the Company sells and the consolidated operating results that are regularly reviewed by the Company’s chief operating decision maker to assess performance and make operating decisions.

Recent Accounting Pronouncements

In May 2011, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2011-04, Amendments to Achieve Common Fair Value Measurement and Disclosure Requirements in U.S. GAAP and IFRSs (“ASU 2011-04”), an update to ASC 820 Fair Value Measurement (“ASC 820”). The amendments in ASU 2011-04 are the result of joint efforts by the FASB and International Accounting Standards Board to develop a single, converged fair value framework and provide converged guidance on how to measure fair value and on what disclosures to provide about fair value measurements. While ASU 2011-04 is largely consistent with existing fair value measurement principles in U.S. GAAP, it expands ASC 820’s existing disclosure requirements for fair value measurements and makes other amendments. Many of these amendments were made to eliminate unnecessary wording differences between U.S. GAAP and International Financial Reporting Standards (“IFRS”). However, some could change how the fair value measurement guidance in ASC 820 is applied. The Company adopted the provisions of ASU 2011-04 on January 1, 2012. The adoption did not have a material impact on the Company’s consolidated financial statements.

In June and December 2011, the FASB issued two ASUs which amend guidance for the presentation of comprehensive income, an update to ASC 220 Comprehensive Income. The amended guidance requires an entity to present components of net income and other comprehensive income in one continuous statement, referred to as the statement of comprehensive income, or in two separate, but consecutive statements. The current option to report other comprehensive income and its components in the statement of stockholders’ equity has been eliminated. Although the new guidance changes the presentation of comprehensive income, there are no changes to the components that are recognized in net income or other comprehensive income under existing guidance. These ASUs were adopted by the Company on January 1, 2012 and changed our financial statement presentation of comprehensive loss, to one continuous statement, but did not impact our net loss, financial position, or cash flows.

In December 2011, the FASB issued ASU No. 2011-11, Balance Sheet (Topic 210): Disclosures about Offsetting Assets and Liabilities. The amendments in this ASU require an entity to disclose information about offsetting and related arrangements to enable users of its financial statements to understand the effect of those arrangements on its financial position. The objective of this disclosure is to facilitate comparison between those entities that prepare their financial statements on the basis of U.S. GAAP and those entities that prepare their financial statements on the basis of IFRS. An entity is required to apply the amendments for annual reporting periods beginning on or after January 1, 2013, and interim periods within those annual periods. An entity should provide the disclosures required by those amendments retrospectively for all comparative periods presented. The Company believes that the adoption of the amendments will not have a material impact on the Company’s consolidated financial statements.