Is that a trademark product or a trademarked product?

Which is correct?
Microsoft has a _______ data summarization product called “PivotTable” although as two words, pivot table is generic.
a. trademarked
b. trademark

Explanation:
As an adjective, trademarked means labeled with proprietary (and legally registered) identification guaranteeing exclusive use.

I came across the incorrect version of my example sentence online today. (Such a rich source of grammatical errors constantly at my fingertips — I am so blessed!) Yet another example of the dropped ed we so often see in things like “old-fashion can ham” and similar products.

Trademarked product. Canned ham. Old-fashioned. And please note: not “old fashioned,” either, which would mean that something was both old and had been created, rather than made in the old style. And you’d need a comma, in any case. Don’t be stingy with the hyphens — they’re cheap.

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