Best Efforts

An agreement an underwriter makes to act as an agent between an issuing company and investors.

Investopedia Says:
In a best efforts agreement, the underwriter agrees to use all efforts to sell as much of an issue as possible to the public. The underwriter can purchase only the amount required to fulfill its client's demand or the entire issue. However, if the underwriter is unable to sell all securities, it is not responsible for any unsold inventory.

Best effort agreements are used mainly for securities with higher risk, such as unseasoned offerings.

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Securities team for underwriting on an Agency basis, usually involving a new offering of securities. The distributor of the securities offered for sale pledges to sell as much as can be sold, but makes no guarantee to purchase the entire offering from the issuer. It may, in fact, be agreeable to sell only part of the total offering, so long as the sale meets the issuer's minimum subscription requirements. If, for example, only three-fifths of an offering is actually sold, the underwriter receives a pro rata share of the total commission and has no further obligation to the issuer. Best effort underwriting is seen most often in the over-the-counter market for initial public offerings by De Novo companies and financial institutions, as opposed to established companies. In Firm Commitment underwriting, the underwriter has given a commitment to purchase the entire offering as Principal in the public offering, and the underwriting risk is borne entirely by the underwriter or investment banking group.