By Carla Mozee, MarketWatch

LONDON (MarketWatch) -- Here are companies whose shares are making notable moves in European trade Tuesday.

Weir Group PLC: Shares of the engineering company climbed 2.9%, topping the FTSE 100, after being upgraded at Credit Suisse to outperform from neutral. Weir could see a roughly 10% upside in fiscal 2016 earnings before interest, taxes and depreciation, in part on improving upstream oil-and-gas markets, analysts said.

IMI PLC: Stock in the engineering company slipped 0.5% following a downgrade by Credit Suisse to neutral from outperform, with analysts saying Weir Group "offers a better relative risk return profile over a two-year horizon," than IMI does.

GAM Holding AG: The investment manager's shares dropped 2.5% after reports David Solo plans to step down as group chief executive on Sept. 8. Solo, who's been in charge since 2004, asked to leave, GAM said in a statement. GAM's board has named Alexander Friedman as Solo's replacement as group CEO.

Luxottica Group SpA: The Italian eye-wear maker fell 0.7% following the departure of Chief Executive Andrea Guerra, who had held the role for nearly 10 years. Guerra told reporters the move comes after differences with founder Leonardo Del Vecchio. Luxottica, which makes Ray-Ban sunglasses, among other brands, will now be run by two co-CEOs.

Vallourec SA: The steel pipe maker was upgraded to buy from neutral at UBS, prompting a 4.3% rise in its shares

The Stoxx Europe 600 was up 0.3% at 343.99.

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