ADTN 10-Q Quarter ended June 30, 2015

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q

For the Quarterly Period Ended June 30, 2015

OR

For the Transition Period from to

Commission File Number 0-24612

ADTRAN, Inc.

(Exact name of Registrant as specified in its charter)

901 Explorer Boulevard, Huntsville, Alabama 35806-2807

(Address of principal executive offices, including zip code)

(256) 963-8000

(Registrant’s telephone number, including area code)

Indicate by check mark whether the Registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding twelve months (or for such shorter period that the Registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes x No ¨

Indicate by check mark whether the Registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulations S-T (232.405 of this chapter) during the preceding 12 months (or for shorter period that the Registrant was required to submit and post such files).    Yes x No ¨

Indicate by check mark whether the Registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a smaller reporting company. See definition of “large accelerated filer”, “accelerated filer”, and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

Indicate by check mark whether the Registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).    Yes ¨ No x

Indicate the number of shares outstanding of each of the issuer’s classes of Common Stock, as of the latest practicable date:

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ADTRAN, Inc.

Quarterly Report on Form 10-Q

For the Three and Six Months Ended June 30, 2015

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FORWARD LOOKING STATEMENTS

The Private Securities Litigation Reform Act of 1995 provides a safe harbor for forward-looking statements made by or on behalf of ADTRAN. ADTRAN and its representatives may from time to time make written or oral forward-looking statements, including statements contained in this report, our other filings with the Securities and Exchange Commission (SEC) and other communications with our stockholders. Generally, the words, “believe,” “expect,” “intend,” “estimate,” “anticipate,” “will,” “may,” “could” and similar expressions identify forward-looking statements. We caution you that any forward-looking statements made by us or on our behalf are subject to uncertainties and other factors that could cause such statements to be wrong. A list of factors that could materially affect our business, financial condition or operating results is included under “Factors that Could Affect Our Future Results” in “Management’s Discussion and Analysis of Financial Condition and Results of Operations” contained in Item 2 of Part I of this report. They have also been discussed in Item 1A of Part I in our most recent Annual Report on Form 10-K for the year ended December 31, 2014 filed on February 24, 2015 with the SEC. Though we have attempted to list comprehensively these important factors, we caution investors that other factors may prove to be important in the future in affecting our operating results. New factors emerge from time to time, and it is not possible for us to predict all of these factors, nor can we assess the impact each factor or a combination of factors may have on our business.

You are further cautioned not to place undue reliance on these forward-looking statements because they speak only of our views as of the date that the statements were made. We undertake no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.

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ADTRAN, INC.

(Unaudited)

(In thousands, except per share amounts)

See notes to consolidated financial statements

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ADTRAN, INC.

(Unaudited)

(In thousands, except per share amounts)

See notes to consolidated financial statements

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ADTRAN, INC.

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME

(Unaudited)

(In thousands)

See notes to consolidated financial statements

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ADTRAN, INC.

(Unaudited)

(In thousands)

See notes to consolidated financial statements

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ADTRAN, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)

(In thousands, except per share amounts)

1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation

The accompanying unaudited consolidated financial statements of ADTRAN ^® , Inc. and its subsidiaries (ADTRAN) have been prepared pursuant to the rules and regulations for reporting on Quarterly Reports on Form 10-Q. Accordingly, certain information and notes required by generally accepted accounting principles for complete financial statements are not included herein. The December 31, 2014 Consolidated Balance Sheet is derived from audited financial statements, but does not include all disclosures required by accounting principles generally accepted in the United States.

In the opinion of management, all adjustments necessary to fairly state these interim statements have been recorded and are of a normal and recurring nature. The results of operations for an interim period are not necessarily indicative of the results for the full year. The interim statements should be read in conjunction with the financial statements and notes thereto included in ADTRAN’s Annual Report on Form 10-K for the year ended December 31, 2014, filed on February 24, 2015 with the SEC.

Changes in Classifications

We reclassified $2.3 million from other receivables to accounts receivable at December 31, 2014 to conform to the current period presentation.

Out of Period Adjustment

In connection with the preparation of our Condensed Consolidated Financial Statements, we recorded corrections of certain out of period, immaterial misstatements that occurred in prior periods, the most significant of which resulted in an increase in Other Expense of $1.3 million in the first quarter of 2015. The aggregate impact of the corrections was a $0.8 million reduction to pre-tax income for the six months ended June 30, 2015 and is not expected to be material to the current year annual results.

Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenue and expense during the reporting period. Our more significant estimates include the obsolete and excess inventory reserves, warranty reserves, customer rebates, determination of the deferred revenue components of multiple element sales agreements, estimated costs to complete obligations associated with deferred revenues, estimated income tax provision and income tax contingencies, the fair value of stock-based compensation, impairment of goodwill, valuation and estimated lives of intangible assets, estimated pension liability, fair value of investments, and the evaluation of other-than-temporary declines in the value of investments. Actual amounts could differ significantly from these estimates.

Recent Accounting Pronouncements

In May 2014, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers (ASU 2014-09), which supersedes the revenue recognition requirements in Topic 605, Revenue Recognition , including most industry-specific revenue recognition guidance throughout the Industry Topics of the Codification. The core principle of ASU 2014-09 is to recognize revenues when promised goods or services are transferred to customers in an amount that reflects the consideration that is expected to be received for those goods or services. ASU 2014-09 is effective for annual reporting periods beginning after December 15, 2017, including interim periods within that reporting period, and early application is not permitted. ASU 2014-09 allows for either full retrospective or modified retrospective adoption. We are currently evaluating the transition method that will be elected and the impact that the adoption of ASU 2014-09 will have on our financial position, results of operations and cash flows.

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In April 2015, the FASB issued Accounting Standards Update No. 2015-05, Intangibles – Goodwill and Other – Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement (ASU 2015-05), which provides guidance on accounting for fees paid by a customer in a cloud computing arrangement. If a cloud computing arrangement includes a software license, then the customer should account for the software license element of the arrangement consistent with the acquisition of other software licenses. If a cloud computing arrangement does not include a software license, the customer should account for the arrangement as a service contract. ASU 2015-05 is effective for annual reporting periods beginning after December 15, 2015, including interim periods within that reporting period. Early adoption is permitted. The amendments may be applied either prospectively to all arrangements entered into or materially modified after the effective date or retrospectively. We do not believe the adoption of ASU 2015-05 will have a material impact on our financial position, results of operations and cash flows.

In July 2015, the FASB issued Accounting Standards Update No. 2015-11, Inventory (Topic 330): Simplifying the Measurement of Inventory (ASU 2015-11) . Currently, Topic 330, Inventory, requires an entity to measure inventory at the lower of cost or market. Market could be replacement cost, net realizable value, or net realizable value less an approximately normal profit margin. ASU 2015-11 does not apply to inventory that is measured using last-in, first-out (LIFO) or the retail inventory method. The amendments apply to all other inventory, which includes inventory that is measured using first-in, first-out (FIFO) or average cost. ASU 2015-11 requires an entity to measure in scope inventory at the lower of cost and net realizable value. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. ASU 2015-11 is effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. The amendments should be applied prospectively with earlier application permitted as of the beginning of an interim or annual reporting period. We do not believe the adoption of ASU 2015-05 will have a material impact on our financial position, results of operations and cash flows.

2. INCOME TAXES

Our effective tax rate increased from 34.2% in the six months ended June 30, 2014 to 39.1% in the six months ended June 30, 2015. The increase in the effective tax rate between the two periods is primarily attributable to the release of a valuation allowance attributable to a foreign subsidiary in 2014.

3. PENSION BENEFIT PLAN

We maintain a defined benefit pension plan covering employees in certain foreign countries.

The following table summarizes the components of net periodic pension cost for the three and six months ended June 30, 2015 and 2014:

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4. STOCK-BASED COMPENSATION

The following table summarizes the stock-based compensation expense related to stock options, restricted stock units (RSUs) and restricted stock for the three and six months ended June 30, 2015 and 2014, which was recognized as follows:

The fair value of our stock options is estimated using the Black-Scholes model. The determination of the fair value of stock options on the date of grant using the Black-Scholes model is affected by our stock price as well as assumptions regarding a number of complex and subjective variables that may have a significant impact on the fair value estimate.

There were no options granted during the three months ended June 30, 2015 and 2014. The weighted-average assumptions and value of options granted for the six months ended June 30, 2015 and 2014 are as follows:

The fair value of our RSUs is calculated using a Monte Carlo Simulation valuation method. No RSUs were granted or vested during the three and six months ended June 30, 2015 and 2014. Twelve thousand RSUs were forfeited during the six months ended June 30, 2015.

The fair value of restricted stock is equal to the closing price of our stock on the date of grant. No restricted stock was granted or forfeited during the three and six months ended June 30, 2015 and 2014. Two thousand shares of restricted stock vested during the three months ended June 30, 2015.

Stock-based compensation expense recognized in our Consolidated Statements of Income for the three and six months ended June 30, 2015 and 2014 is based on options, RSUs and restricted stock ultimately expected to vest, and has been reduced for estimated forfeitures. Estimated forfeitures for stock options are based upon historical experience and approximate 3.3% annually. We estimated a 0% forfeiture rate for our RSUs and restricted stock due to the limited number of recipients and historical experience for these awards.

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As of June 30, 2015, total compensation expense related to non-vested stock options, RSUs and restricted stock not yet recognized was approximately $12.6 million, which is expected to be recognized over an average remaining recognition period of 2.5 years.

The following table is a summary of our stock options outstanding as of December 31, 2014 and June 30, 2015 and the changes that occurred during the six months ended June 30, 2015:

The aggregate intrinsic values in the table above represent the total pre-tax intrinsic value (the difference between the closing price of our stock on the last trading day of the quarter and the exercise price, multiplied by the number of in-the-money options) that would have been received by the option holders had all option holders exercised their options on June 30, 2015. The aggregate intrinsic value will change based on the fair market value of our stock.

The total pre-tax intrinsic value of options exercised during the three and six months ended June 30, 2015 was $25 thousand and $0.1 million, respectively.

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5. INVESTMENTS

At June 30, 2015, we held the following securities and investments, recorded at either fair value or cost.

At December 31, 2014, we held the following securities and investments, recorded at either fair value or cost.

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As of June 30, 2015, our corporate bonds and municipal fixed-rate bonds had the following contractual maturities:

Actual maturities may differ from contractual maturities because some borrowers have the right to call or prepay obligations with or without call or prepayment penalties.

Our investment policy provides limitations for issuer concentration, which limits, at the time of purchase, the concentration in any one issuer to 5% of the market value of our total investment portfolio.

At June 30, 2015, we held a $30.0 million restricted certificate of deposit, which is carried at cost. This investment serves as a collateral deposit against the principal amount outstanding under loans made to ADTRAN pursuant to an Alabama State Industrial Development Authority revenue bond (the Bond). At June 30, 2015, the estimated fair value of the Bond using a level 2 valuation technique was approximately $29.9 million, based on a debt security with a comparable interest rate and maturity and a Standard and Poor’s credit rating of AAA. For more information on the Bond, see “Debt” under “Liquidity and Capital Resources” in the “Management’s Discussion and Analysis of Financial Condition and Results of Operations” contained in Item 2 of Part I of this report.

We review our investment portfolio for potential “other-than-temporary” declines in value on an individual investment basis. We assess, on a quarterly basis, significant declines in value which may be considered other-than-temporary and, if necessary, recognize and record the appropriate charge to write-down the carrying value of such investments. In making this assessment, we take into consideration qualitative and quantitative information, including but not limited to the following: the magnitude and duration of historical declines in market prices, credit rating activity, assessments of liquidity, public filings, and statements made by the issuer. We generally begin our identification of potential other-than-temporary impairments by reviewing any security with a fair value that has declined from its original or adjusted cost basis by 25% or more for six or more consecutive months. We then evaluate the individual security based on the previously identified factors to determine the amount of the write-down, if any. For the three and six months ended June 30, 2015 and 2014, other-than-temporary impairment charges were not significant.

Realized gains and losses on sales of securities are computed under the specific identification method. The following table presents gross realized gains and losses related to our investments.

As of June 30, 2015 and 2014, gross unrealized losses related to individual securities in a continuous loss position for 12 months or longer were not significant.

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We have categorized our cash equivalents held in money market funds and our investments held at fair value into a three-level fair value hierarchy based on the priority of the inputs to the valuation technique for the cash equivalents and investments as follows: Level 1—Values based on unadjusted quoted prices for identical assets or liabilities in an active market; Level 2—Values based on quoted prices in markets that are not active or model inputs that are observable either directly or indirectly; Level 3—Values based on prices or valuation techniques that require inputs that are both unobservable and significant to the overall fair value measurement. These inputs include information supplied by investees.

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The fair value of our Level 2 securities is calculated using a weighted average market price for each security. Market prices are obtained from a variety of industry standard data providers, security master files from large financial institutions, and other third-party sources. These multiple market prices are used as inputs into a distribution-curve-based algorithm to determine the daily market value of each security.

Our municipal variable rate demand notes have a structure that implies a standard expected market price. The frequent interest rate resets make it reasonable to expect the price to stay at par. These securities are priced at the expected market price.

6. DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES

We have certain customers and suppliers who are invoiced or pay in a non-functional currency. Changes in the monetary exchange rates may adversely affect our results of operations and financial condition. When appropriate, we enter into various derivative transactions to enhance our ability to manage the volatility relating to these typical business exposures. We do not hold or issue derivative instruments for trading or other speculative purposes. Our derivative instruments are recorded in the Consolidated Balance Sheets at their fair values. Our derivative instruments do not qualify for hedge accounting, and accordingly, all changes in the fair value of the instruments are recognized as other income (expense) in the Consolidated Statements of Income. The maximum contractual period for our derivatives is currently less than twelve months. Our derivative instruments are not subject to master netting arrangements and are not offset in the Consolidated Balance Sheets.

As of June 30, 2015, we had forward contracts outstanding with notional amounts totaling €39.0 million ($43.4 million), which mature at various times throughout 2015.

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The fair values of our derivative instruments recorded in the Consolidated Balance Sheet as of June 30, 2015 and December 31, 2014 were as follows:

The change in the fair values of our derivative instruments recorded in the Consolidated Statements of Income during the three and six months ended June 30, 2015 and 2014 were as follows:

7. INVENTORY

At June 30, 2015 and December 31, 2014, inventory consisted of the following:

We establish reserves for estimated excess, obsolete, or unmarketable inventory equal to the difference between the cost of the inventory and the estimated fair value of the inventory based upon assumptions about future demand and market conditions. At June 30, 2015 and December 31, 2014, raw materials reserves totaled $17.6 million and $16.9 million, respectively, and finished goods inventory reserves totaled $7.6 million and $7.8 million, respectively.

8. GOODWILL AND INTANGIBLE ASSETS

Goodwill, all of which relates to our acquisition of Bluesocket, Inc. and is included in our Enterprise Networks division, was $3.5 million at June 30, 2015 and December 31, 2014. We evaluate the carrying value of goodwill during the fourth quarter of each year and between annual evaluations if events occur or circumstances change that would more likely than not reduce the fair value of the reporting unit below its carrying amount. We have elected to first assess the qualitative factors to determine whether it is more likely than not that the fair value of the reporting unit to which the goodwill is assigned is less than its carrying amount as a basis for determining whether it is necessary to perform the two-step impairment test. If we determine that it is more likely than not that its fair value is less than its carrying amount, then the two-step impairment test will be performed. There have been no impairment losses recorded since acquisition.

Intangible assets are included in other assets in the accompanying Consolidated Balance Sheets and include intangibles acquired in conjunction with our acquisitions of Objectworld Communications Corporation on September 15, 2009, Bluesocket, Inc. on August 4, 2011, and the NSN BBA business on May 4, 2012.

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The following table presents our intangible assets as of June 30, 2015 and December 31, 2014:

Amortization expense, all of which relates to business acquisitions, was $0.5 million and $0.6 million for the three months ended June 30, 2015 and 2014, respectively, and $1.0 million and $1.2 million for the six months ended June 30, 2015 and 2014, respectively.

As of June 30, 2015, the estimated future amortization expense of our intangible assets is as follows:

9. STOCKHOLDERS’ EQUITY

A summary of the changes in stockholders’ equity for the six months ended June 30, 2015 is as follows:

Stock Repurchase Program

Since 1997, our Board of Directors has approved multiple share repurchase programs that have authorized open market repurchase transactions of up to 45.0 million shares of our common stock. During the six months ended June 30, 2015, we repurchased 2.9 million shares of our common stock at an average price of $16.87 per share. As of June 30, 2015, we have the authority to purchase an additional 1.9 million shares of our common stock under the current plans approved by the Board of Directors.

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Stock Option Exercises

We issued 0.1 million shares of treasury stock during the six months ended June 30, 2015 to accommodate employee stock option exercises. The stock options had exercise prices ranging from $15.29 to $22.53. We received proceeds totaling $0.8 million from the exercise of these stock options during the six months ended June 30, 2015.

Dividend Payments

During the six months ended June 30, 2015, we paid cash dividends as follows (in thousands except per share amounts):

Other Comprehensive Income

Other comprehensive income consists of unrealized gains (losses) on available-for-sale securities, reclassification adjustments for amounts included in net income related to impairments of available-for-sale securities, realized gains (losses) on available-for-sale securities, and amortization of actuarial gains (losses) related to our defined benefit plan, defined benefit plan adjustments, and foreign currency translation adjustments.

The following tables present changes in accumulated other comprehensive income, net of tax, by component for the three months ended June 30, 2015 and 2014:

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The following tables present changes in accumulated other comprehensive income, net of tax, by component for the six months ended June 30, 2015 and 2014: