Our investments are carried at fair value in accordance with the 1940 Act and SFAS No. 157, Fair Value Measurements ("SFAS No. 157"). In accordance with the 1940 Act, unrestricted minority-owned publicly traded securities for which market quotations are readily available are valued at the closing market quote on the valuation date and majority-owned publicly traded securities and other privately held securities are valued as determined in good faith by our Board of Directors. For securities of companies that are publicly traded for which we have a majority-owned interest, the value is based on the closing market quote on the valuation date plus a control premium if our Board of Directors determines in good faith that additional value above the closing market quote would be obtainable upon a sale or transfer of our controlling interest.
We adopted SFAS No. 157 on January 1, 2008. SFAS No. 157 provides a framework for measuring the fair value of assets and liabilities. SFAS No. 157 also provides guidance regarding a fair value hierarchy, which prioritizes information used to measure fair value and the effect of fair value measurements on earnings and provides for enhanced disclosures determined by the level within the hierarchy of information used in the valuation. SFAS No. 157 applies whenever other standards require (or permit) assets or liabilities to be measured at fair value but does not expand the use of fair value in any new circumstances.
SFAS No. 157 defines fair value in terms of the price that would be received upon the sale of an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (the "exit price") and excludes transaction costs. Under SFAS No. 157, the fair value measurement also assumes that the transaction to sell an asset occurs in the principal market for the asset or, in the absence of a principal market, the most advantageous market for the asset. The principal market is the market in which the reporting entity would sell or transfer the asset with the greatest volume and level of activity for the asset. In determining the principal market for an asset or liability under SFAS No. 157, it is assumed that the reporting entity has access to the market as of the measurement date.
The market in which we would sell our private finance investments is the mergers and acquisition ("M&A") market. Under SFAS No. 157, we have indentified the M&A market as our principal market for portfolio companies only if we have the ability to initiate a sale of the portfolio company as of the measurement date. We decide whether we have the ability to initiate a sale of a portfolio company based on our ability to control or gain control of the board of directors of the portfolio company as of the measurement date. In evaluating if we can control or gain control of a portfolio company as of the measurement date, we include our equity securities and those securities held by entities managed by American Capital, LLC, on a fully diluted basis. For investments in securities of portfolio companies for which we do not have the ability to control or gain control as of the measurement date and for which there is no active market, our principal market is a hypothetical secondary market to determine fair value.
Accordingly, we use the M&A market as our principal market for portfolio companies that we control or can gain control as of the measurement date, and we use a hypothetical secondary market for portfolio companies that we do not control or cannot gain control as of the measurement date. To the extent that an active market exists, we will consider that as our principal market. Our valuation policy considers the fact that no ready market exists for substantially all of the securities in which we invest and that fair value for our investments must typically be determined using unobservable inputs.
Enterprise Value Waterfall Methodology
For securities of portfolio companies that we have identified the M&A market as the principal market, we estimate the fair value based on the enterprise value waterfall ("Enterprise Value Waterfall") valuation methodology. Under the Enterprise Value Waterfall valuation methodology, we estimate the enterprise value of the portfolio company and then waterfall the enterprise value over the portfolio company's securities in order of their preference relative to one another. For minority equity securities, we also estimate the fair value using the Enterprise Value Waterfall valuation methodology. In using the Enterprise Value Waterfall valuation methodology, we considered the in-use valuation premise under SFAS No. 157, which assumes the debt and equity securities are sold together, and which we believe is appropriate as this would provide the maximum proceeds to the seller. In applying the Enterprise Value Waterfall valuation methodology, we also considered that in a change of control transaction, our debt securities are generally required to be repaid and that a buyer cannot assume the debt security.
To estimate the enterprise value of the portfolio company, we prepare an analysis consisting of traditional valuation methodologies including market income and cost approaches. We weight some or all of the traditional valuation methods based on the individual circumstances of the portfolio company in order to conclude on our estimate of the enterprise value. The methodologies consist of valuation estimates based on: valuations of comparable public companies, recent sales of private and public comparable companies, discounting the forecasted cash flows of the portfolio company, estimating the liquidation or collateral value of the portfolio company's assets, third party valuations of the portfolio company, considering offers from third parties to buy the company, estimating the value to potential strategic buyers and considering the value of recent investments in the equity securities of the portfolio company.
In valuing convertible debt, equity or other similar securities, we value our investment based on our pro rata share of the residual equity value available after deducting all outstanding debt from the estimated enterprise value. We value non-convertible debt securities at the face amount of the debt to the extent that the estimated enterprise value of the portfolio company exceeds the outstanding debt of the portfolio company. If the estimated enterprise value is less than the outstanding debt of the company, we reduce the value of our debt investment beginning with the junior most debt such that the enterprise value less the value of the outstanding debt is zero.
Market Yield Valuation Methodology
For securities of portfolio companies for which we have identified the hypothetical secondary market as the principal market, we determine the fair value based on the assumptions that hypothetical market participants would use to value the security using a market yield ("Market Yield") valuation methodology based on an exchange valuation premise under SFAS No. 157.
For debt and redeemable preferred equity securities of our private finance portfolio for which we do not control or cannot gain control as of the measurement date, we estimate the fair value based on such factors as third party broker quotes and our own assumptions in the absence of market observable data, including synthetic credit ratings, estimated remaining life, current market yield and interest rate spreads of similar securities as of the measurement date.
We also value our investments in Structured Products using the Market Yield valuation methodology. We estimate the fair value based on such factors as third party broker quotes and cash flow forecasts subject to market participant assumptions regarding the investments' underlying collateral including, but not limited to, assumptions of default and recovery rates, reinvestment spreads and prepayment rates. Cash flow forecasts are discounted using a market participants market yield assumptions that are derived from multiple sources including, but not limited to, third party broker quotes, recent investments and securities with similar structure and risk characteristics.
Interest Rate Derivatives
For interest rate derivative agreements, we estimate the fair value based on the estimated net present value of the future cash flows using a forward interest rate yield curve in effect as of the measurement period, adjusted for nonperformance risk, if any, including a quantitative and/or qualitative evaluation of both our credit risk and our counterparty's credit risk.
Due to the uncertainty inherent in the valuation process, such estimates of fair value may differ significantly from the values that would have been used had a ready market for the securities existed, and the differences could be material. Additionally, changes in the market environment and other events that may occur over the life of the investments may cause the gains or losses ultimately realized on these investments to be different than the valuations currently assigned.