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Invesco Ltd., the Atlanta-based investment management company, has been sued by a Boston-based trust claiming infringement of its trademarks for exchange- traded funds.
Select Sector SPDR Trust said Invesco began marketing its PowerShares funds using the same XL ticker symbols SPDR has been using, in a complaint filed today in U.S. District Court in Houston.

Intrestingly, SPDR is a registered trademark of Standard & Poor’s.
Complaint SPDR Invesco Ticker Symbol Trademark