For a product like Poser its business behaves like a swing.
A large loyal user base is attractive enough to entice large companies to buy it but then it doesn't develop in the way they had hoped so they want to get rid of it again. The original developers still believe in the product so they take it over in a management buyout. The this new small company finds the going hard so they are looking for capital. And the circle is closed we start over again.
The problem with niche products is that they require a lot of capital to keep going and develop new releases but money only comes in in leaps and bounds (with the new release). This makes it very hard to properly manage the cash flow. The large user base and the profits with a new release are interesting for large companies but these require a steady return on investment to keep going and a product like Poser might not return the big money between releases (which can be years apart). So whenever the big company needs to improve their baseline they look for their historically weak products and tries to dump them (traditionally Poser being one of those weak products). After a lot of arm wrestling someone take the product over, releases a new version, makes enough to pay for the product and runs out of money 1 or 2 years later (generally shortly before the next new version).