Other NPEs, however, strategically assert valid patents against actual infringers, often in collaboration with independent inventors.

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Cross-licensing giants naturally view NPEs that help inventors as a threat, perhaps an even greater threat than trolls.

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At least two other cases pit RIM against so-called non-practicing entities, or NPEs.

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These NPEs must uncover evidence of infringement, rule out prior art and inequitable conduct, and interact at length with the patent office.

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NPEs are companies that generate revenue solely by licensing and litigating patents.

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One great justification for NPEs is that they can provide the actual capital and willingness to defend property rights where an inventor simply cannot.

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In response, NPEs say they encourage innovation by rewarding small inventors and by helping to make a market for patents, which also makes it easier to manage the risk of investments in applied research.

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They have just one ally in the current patent litigation landscape: NPEs that have the expertise to determine the validity of their claim, and the resources necessary to pursue it to a final judgment of infringement.

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