(Sharecast News) - Activist investor Richard Bernstein is reportedly calling for a sale of London-listed filtration group Porvair.
According to Sky News, Bernstein - founder and former investment manager of Crystal Amber - has written to Porvair chairman John Nicholas urging him to explore strategic alternatives for the company.

His intervention comes after a lacklustre year for Porvair's shares, Sky said.

The company comprises a group of specialist filtration, laboratory and environmental technology companies whose products are used by industries such as aerospace.

According to Sky, Bernstein, who has a small stake in Porvair in a personal capacity, said the company was "an attractive business currently valued by the stock market at substantially below its strategic value".

"Now is the time for the board to release value by actively engaging in strategic alternatives," he added.

"The scale of shareholder frustration is evidenced by significant 24% per vote against the chairman's re-election."

At 1230 BST, Porvair shares were up 3.5% at 774p.

• News Channel