Affymax, Inc. (AFFY)

[aquaspin]

Found it. AFFY did have ownership change:

Affymax adopts tax benefit preservation plan Affymax announced that its board has adopted a Tax Benefit Preservation Plan, or Rights Plan, in an effort to preserve the value of its significant net operating loss carryforwards, or NOLs, in relation to the potential limitations under Section 382 of the Internal Revenue Code. The company had federal NOLs totaling approximately $481M at December 31, 2013, a substantial portion of which are limited due to a prior 'ownership change[color=red][/color]'. The company's use of the remaining NOLs could be substantially limited if the company experiences another 'ownership change'. In general, an ownership change occurs if there is a cumulative change in a company's ownership by '5% shareholders' that increases by more than 50 percentage points over the lowest percentage owned by such stockholders at any time during the prior three years on a rolling basis. The company noted that the Rights Plan is designed to serve the interests of all stockholders by helping to protect the company's ability to use its NOLs to offset future tax liabilities and is similar to plans adopted by other companies with significant tax attributes.