In a note to clients issued Tuesday, J.P. Morgan’s data networking team smelled danger in Monday’s report that Apple (AAPL) and Google (GOOG) have bid on part of the patent portfolio being auctioned off in the wake of Nortel Networks’ January 2009 bankruptcy.

There are more than 4,000 patents at stake, organized into six “buckets” by related technologies, but Apple and Google are said to have their eye on the filings that cover Nortel’s work in so-called Long Term Evolution wireless communications. Also known as 4G, LTE is seen by many as the protocol around which the next generation of smartphones will be built.

“Given the strong cash positions of AAPL and GOOG and the relatively limited patent portfolios of both we are concerned that prices could get bid up,” writes J.P. Morgan’s Rod Hall. “We believe embattled vendors like NOK, MOT and RIMM might find it difficult to cede these patents without a fight.”

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