Pues sí, MS tuvo en su momento una parte de las acciones de Apple.
De la wikipedia inglesa:
Cita: At the 1997 Macworld Expo, Steve Jobs announced that Apple would be entering into partnership with Microsoft. Settlement discussions regarding Apple's "Look and Feel" lawsuit and the QuickTime piracy lawsuit resulted in a five-year commitment from Microsoft to release Microsoft Office for Macintosh as well as a US$150 million investment in non-voting Apple stock. (This event is often inaccurately described as a "bailout" of Apple by Microsoft. At the time Apple had a little over US$1 billion in cash and cash equivalents according to their 10-Q statement.[29] Microsoft later sold its shares for a tidy profit.)