Subsequent Offering
  
See: Secondary Offering.
Subsequent. As in: the next in a sequence. What this term usually refers to is a series of money-raisings that are linked by coming from the same company, or the same class or type of offering.
Whatever.com completed its IPO. Its stock was then liquidly trading. 6 months and change passed, and now insiders want to sell and buy Porsches. So the company has a secondary offering: an offering subsequent to their IPO and the insiders...offering their shares for sale to a hungrily buying public.