This week Facebook announced that an investor agreed to acquire up to $100 million of common stock from Facebook employees, which as I observed is a unique opportunity for private company employees.

Investors sometimes permit founders to achieve liquidity with respect to a portion of their equity holdings. This is typically accomplished either through the investor’s direct purchase from the founder of some of the founder’s common stock or by the company’s use of the funds invested by the investor to redeem a portion of the founder’s common stock. Facebook’s transaction is unique in that it extends this founder liquidity concept to employees, who typically have to wait for a company sale or public offering to achieve liquidity. Presumably Facebook’s board and management helped to negotiate this arrangement to reward long-time employees who have contributed to the company’s valuation growth over the past few years.

Such a transaction must comply with applicable securities laws and presumably includes an express acknowledgement by each selling employee that he or she realizes that the value of the shares being sold could rise and a release of all claims to any such future appreciation. While the Facebook transaction is very unique, given the state of the public markets such transactions may become more common.