Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2017

Consolidation, Policy [Policy Text Block]

Principles of Consolidation

The accompanying consolidated financial statements include the accounts of ClearSign and its subsidiary.

Use Of Estimates, Policy [Policy Text Block]

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 certain 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. Actual results could differ from those estimates.

Revenue Recognition, Policy [Policy Text Block]

Revenue Recognition, Cost of Sales and Change in Accounting Principle

In September 2014, the Financial Accounting Standards Board issued Accounting Standards Update No. 2014-09 (ASU No. 2014-09) regarding revenue recognition. The new standard provides authoritative guidance clarifying the principles for recognizing revenue and developing a common revenue standard for U.S. generally accepted accounting principles. The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods and services to customers in an amount that reflects the consideration to which the entity expects to be entitled in the exchange for those goods or services. Additionally, the guidance requires improved disclosure to help users of financial statements better understand the nature, amount, timing, and uncertainty of revenue that is recognized. It is effective January 1, 2018 and early adoption is permitted. Management has elected early adoption of this standard to minimize the eventual cost of implementation.

The Company previously accounted for revenues from design and installation of its products on the completed contract method. Revenues from contracts and related costs of goods sold were recognized once the contract was completed or substantially completed. Contract costs included all direct material and labor costs and those indirect costs related to contract performance, such as indirect labor, supplies, and depreciation costs. Provisions for estimated losses on uncompleted contracts were made in the period in which such losses were determined.

The Company retroactively adopted ASU No. 2014-09 effective January 1, 2017. The Company reviewed each contract to identify contract rights, performance obligations, and transaction prices, including the allocation of prices to separate performance obligations. Revenues and costs of sales are recognized once the goods or services are delivered to the customer’s control and performance obligations are satisfied. Typically, the Company’s customer contracts include performance obligations related to emission levels or other metrics that are measured at project completion. Management analyzed prior year revenue recognition made under the completed contract method and determined that no changes in the previously reported financial statements were required. Management elected to not apply the practical expedients in the adoption of ASU No. 2014-09.

The Company’s contracts with customers have performance obligations regarding air emissions and operational performance that are satisfied upon completion of service. Since this is the singular performance obligation and cannot be achieved until the air emissions and operational performance have been successfully tested, revenue related to the contracts is recognized upon project completion.

The Company’s contracts generally include progress payments from the customer upon completion of defined milestones. As these payments are received they are offset against accumulated project costs and recorded as either contract assets or contract liabilities. Upon completion of the performance obligations and acceptance by the customer the projects can be recorded as revenue. The Company has recognized revenue of $540,000 and $621,000 in 2017 and 2016 respectively.

The Company's contracts with customers contain no variable considerations or incentives or discounts that would cause revenue to be allocated or adjusted over time. Therefore, no separate methods of evaluating the contracts other than consideration of the price at achievement of the performance objectives was used in satisfying the review requirements of ASU No. 2014-09.

Contract Acquisition Costs And Practical Expedients Policy [Policy Text Block]

Contract acquisition costs and practical expedients

For contracts that have a duration of less than one year, the Company follows ASC 606, practical expedients and expenses those costs when incurred; for contracts with a life exceeding one year, the Company records those costs when performance obligations related to the contract are completed. The Company generally expenses sales commissions when earned. The Company records those costs within general and administrative expenses.

Standard Product Warranty, Policy [Policy Text Block]

Product Warranties

The Company warrants all installed products against defects in materials and workmanship for a period specified in each contract by replacing failed parts. Accruals for product warranties are based on historical warranty experience and current product performance trends, and are recorded at the time revenue is recognized as a component of cost of sales. The warranty liabilities are reduced by material and labor costs used to replace parts over the warranty period in the periods in which the costs are incurred. The Company periodically assesses the adequacy of its recorded warranty liabilities and adjusts the amounts as necessary, and such adjustments could be material in the future if estimates differ significantly from actual warranty expense. The warranty liabilities are included in accrued liabilities in the balance sheets.

Cash and Cash Equivalents, Policy [Policy Text Block]

Cash and Cash Equivalents

Highly liquid investments purchased with an original maturity of three months or less are considered cash equivalents. Cash is maintained with a commercial bank where accounts are generally guaranteed by the Federal Deposit Insurance Corporation up to $250,000. The Company’s deposits may at times exceed this limit. The Company has not experienced losses in such accounts and believes it is not exposed to any significant credit risk on cash and cash equivalents.

Receivables, Trade and Other Accounts Receivable, Allowance for Doubtful Accounts, Policy [Policy Text Block]

Accounts Receivable and Allowance for Doubtful Accounts

Accounts receivable are recorded at the invoiced amount. An allowance for doubtful accounts is established, as necessary, based on past experience and other factors which, in management’s judgment, deserve current recognition in estimating bad debts. The determination of the collectability of amounts due from customer accounts requires the Company to make judgments regarding future events and trends. Allowances for doubtful accounts are determined based on assessing the Company’s portfolio on an individual customer and on an overall basis. This process consists of a review of historical collection experience, current aging status of the customer accounts, and the financial condition of the Company’s customers. Based on a review of these factors, the Company may establish or adjust the allowance for specific customers and the accounts receivable portfolio as a whole.

Fixed Assets Policy [Policy Text Block]

Fixed Assets and Change in Accounting Principle for Leases

Fixed assets are recorded at cost. As disclosed in Note 3, in 2017 the Company retroactively adopted Accounting Standards Update No. 2016-02 (ASU No. 2016-02) regarding leases. For those leases with a term greater than one year, the Company recognizes on the balance sheet at the time of lease inception or modification a right-of-use asset and a lease liability, initially measured at the present value of the lease payments. Lease costs are recognized in the income statement over the lease term on a straight-line basis. Operating leases with a term of 1 year or less (short term leases) are recognized on a straight line basis over the term. Depreciation is computed using the straight-line method over the estimated useful lives of the respective assets. Leasehold improvements are depreciated over the life of the lease or their useful life, whichever is shorter. All other fixed assets are depreciated over two to four years. Maintenance and repairs are expensed as incurred.

Patents and Trademarks Policy [Policy Text Block]

Patents and Trademarks

Patents and trademarks are recorded at cost. Amortization is computed using the straight-line method over the estimated useful lives of the assets once they are awarded.

Impairment Of Long Lived Asset Policy [Policy Text Block]

Impairment of Long-Lived Assets

The Company tests long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable through the estimated undiscounted cash flows expected to result from the use and eventual disposition of the assets. In that event, a loss is recognized based on the amount by which the carrying amount exceeds the fair value of the long-lived assets. Fair value is determined based on the present value of estimated expected cash flows using a discount rate commensurate with the risks involved, quoted market prices, or appraised values depending upon the nature of the assets. Loss on long-lived assets to be disposed of is determined in a similar manner, except that fair values are reduced for the cost of disposal.

Fair Value Of Financial Instruments, Policy [Policy Text Block]

Fair Value of Financial Instruments

Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Assets and liabilities measured at fair value are categorized based on whether or not the inputs are observable in the market and the degree that the inputs are observable. The categorization of financial assets and liabilities within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement. The three levels of inputs used to establish fair value are the following:

Level 1 – Quoted prices in active markets for identical assets or liabilities,

Level 2 – Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities; and

Level 3 – Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

The Company's financial instruments primarily consist of cash and cash equivalents, accounts payable and accrued expenses. As of the balance sheet dates, the estimated fair values of the financial instruments were not materially different from their carrying values as presented on the balance sheets. This is primarily attributable to the short term maturities of these instruments.

In adopting ASU 2016-02 as described in Note 3, the Company recorded lease liabilities for the estimated present value of the lease payments under the lease agreements. The Company determined the interest rate based on an estimated incremental borrowing rate. The lease liabilities are classified within Level 3.

The Company did not identify any other non-recurring assets and liabilities that are required to be presented in the balance sheets at fair value.

Research and Development Expense, Policy [Policy Text Block]

Research and Development

The cost of research and development is expensed as incurred. Research and development costs consist of salaries, benefits, share based compensation, consulting fees, rent, utilities, depreciation, and consumables.

Income Tax, Policy [Policy Text Block]

Income Taxes

The Company accounts for income taxes using an asset and liability approach which allows for the recognition and measurement of deferred tax assets based upon the likelihood of realization of tax benefits in future years. Under the asset and liability approach, deferred taxes are provided for the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. A valuation allowance is provided for deferred tax assets if it is more likely than not these items will either expire before the Company is able to realize their benefits, or that future deductibility is uncertain. Tax benefits from an uncertain tax position are recognized only if it is more likely than not that the tax position will be sustained on examination by the taxing authorities based on the technical merits of the position. The tax benefits recognized in the consolidated financial statements from such a position are measured based on the largest benefit that has a greater than 50 percent likelihood of being realized upon ultimate resolution.

Share-Based Compensation, Option and Incentive Plans Policy [Policy Text Block]

Stock-Based Compensation

The costs of all employee stock options, as well as other equity-based compensation arrangements, are reflected in the consolidated financial statements based on the estimated fair value of the awards on the grant date. That cost is recognized over the period during which an employee is required to provide service in exchange for the award. Stock compensation for stock granted to non-employees is determined as the fair value of the consideration received or the fair value of equity instruments issued, whichever is more reliably measured.

Earnings Per Share, Policy [Policy Text Block]

Net Loss per Common Share

Basic loss per share is computed by dividing loss available to common stockholders by the weighted-average number of common shares outstanding. Diluted loss per share is computed similar to basic loss per share except that the denominator is increased to include additional common shares available upon exercise of stock options and warrants using the treasury stock method, except for periods for which no common share equivalents are included because their effect would be anti-dilutive. At December 31, 2017 and 2016, potentially dilutive shares outstanding amounted to 3,489,644 and 1,328,128, respectively.

In connection with the January 2017 rights offering (see Note 8), the company evaluated the financial impact of FASB ASC 260, “Earnings per Share,” which states, among other things, that if a rights issue is offered to all existing stockholders at an exercise price tht is less than the fair value of the stock, then the weighted average shares outstanding and basic and diluted earnings per share shall be adjusted retroactively to reflect the bonus element of the rights offering for all periods presented. The Company determined that the application of this specific provision of ASC 260 was immaterial to previously issued financial statements and therefore, did not retroactively adjust previously reported weighted average shares outstanding and basic and diluted earnings per share.

Recently Adopted Standards [Policy Text Block]

Recently Issued Accounting Pronouncements

In May, 2017 the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2017-09 Scope of Modification Accounting, clarifies Topic 718, Compensation – Stock Compensation, which requires a company to apply modification accounting to changes in the terms or conditions of a share-based payment award unless all of the following criteria are met: (1) the fair value of the modified award is the same as the fair value of the original award immediately before the modification. The ASU indicates that if the modification does not affect any of the inputs to the valuation technique used to value the award, the entity is not required to estimate the value immediately before and after the modification; (2) the vesting conditions of the modified award are the same as the vesting conditions of the original award immediately before the modification; and (3) the classification of the modified award as an equity instrument or a liability instrument is the same as the classification of the original award immediately before the modification. The ASU is effective for all entities for fiscal years beginning after December 15, 2017, including interim periods within those years. Early adoption is permitted, including adoption in an interim period. The Company currently does not have any modifications to existing stock compensation agreements and will be able to calculate the impact of the ASU once modifications arise.

Management does not believe that any other recently issued, but not yet effective, authoritative guidance, if currently adopted, would have a material impact on the Company’s consolidated financial statement presentation or disclosures.

Growing Company [Policy Text Block]

Emerging Growth Company

The Company was an emerging growth company as defined under the Jumpstart Our Business Startups Act of 2012 (JOBS Act). An emerging growth company may delay the adoption of certain accounting standards until those standards would otherwise apply to private companies. The Company’s status as an emerging growth company expired December 31, 2017.