Microsoft really don't need it. It would be very hard to argue in court that you released a product called 'Windows' without knowing that a similar product from Microsoft already exists, or that you didn't know that your Windows logo is the same or similar to what Microsoft produce.
Microsoft really should just have a subscript in the EULA or splash screen with "Microsoft® and the Windows Logo ™ are registered trademarks of Microsoft Inc. 1 Redmond Way, Redmond, WA, etc."
That is what startups should do as well. The best way to estalish your intellectual property is through soft enforcement, just sending out polite letters whenever somebody uses your marks in their own products. If they don't change, then pursuit further, but this works well with Facebook and in a lot of other cases.
Microsoft is probably aggressive about the windows trademark as it is a very generic trademark and could easily be revoked if not defended vigorously.
Even in relation to operating systems it is generic - think "window manager". Because of this it is very easy to argue that Microsoft should not have been allowed to trademark such a generic term.
A large part of it is probably a CYA attitude by the legal department, too.
If they're too conservative, and legal notices are featured prominently without reason, the price is paid by Microsoft as a whole having mediocre branding, and the legal team is not accountable. But if the trademarks slip away because they've been too liberal, heads will roll.
Thus the incentives are pretty clearly stacked up for the lawyers to insist on protection that minimizes risk to a degree that hurts Microsoft as a whole.
The trademark symbols can provide constructive notice of the registrant's ownership of the mark, and can be used to support enhanced damages for willful infringement which may not be available in the absence of marking.
Microsoft really should just have a subscript in the EULA or splash screen with "Microsoft® and the Windows Logo ™ are registered trademarks of Microsoft Inc. 1 Redmond Way, Redmond, WA, etc."
That is what startups should do as well. The best way to estalish your intellectual property is through soft enforcement, just sending out polite letters whenever somebody uses your marks in their own products. If they don't change, then pursuit further, but this works well with Facebook and in a lot of other cases.