Patent expenditure among R&D companies

Another reader's request: a correspondent writes to the IPKat:

"Some time ago I saw some research into the typical spend of R&D [note for new readers: that's Research and Development and NOT, despite the current economic climate, Redundancies & Dismissals] biased companies on patents which was then measured against their annual revenue.  Of course, now that I want to read up on the subject, I cannot find any reference to those figures.

Does this ring any bells with you? If you could point me at any such data of which you are aware it would be most helpful".

The IPKat's readers, collectively, are hugely knowledgeable. Any ideas? If so, please email the IPKat here and let him know.  Merpel adds, this is presumably what R&D biased companies spend on getting their patents in the first place, not what it costs to enforce them.