I used 30% because my old stockbroker showed me that it was almost impossible for a company with 30% of the shares to be stopped in any move they care to make. If a BP gets a 30% position you can bet that other Institutional investors will grab a substantial position as well. The BP will easily convince enough of the Institutional investors to vote with them on any issue that no amount of individual investors being against it will defeat them.
I believe a case can be made for a partner making a greater profit on owning a percentage of a small company stock will grow dramatically over acquiring the company and adding to their potentially blockbuster products. At some point the company might be bought out, whether it's by the 30% owner, or another company.
Roche has frequently bought into companies, acquired them completely, then spun them off again. In Genentech's case, Roche did it twice, and Genentech is still operating in such a manner that Roach could easily do it again. Of course each time they do it, they maintain enough of an interest that they can't be beaten in a vote to acquire them again. Investors have done well in the stock, and Roche made a lot of money in all the manipulations.
Gary
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