Grifols (OTCPK:GIFOF) Class B shares came under pressure in Madrid on Thursday after Spanish newspaper Expansion reported that Canadian asset manager Brookfield is seeking a lower price for that category of stock in its proposed take-private bid.

Since the buyout offer led by the Grifols founding family and Brookfield came to light, traders have speculated that the firm’s voting Class A and non-voting Class B stocks will fetch a similar price in an acquisition.

As a result, Class B stock, which trades at a discount to Class A, has outperformed as Grifols (NASDAQ:GRFS) articles of association state that a Class B share shall be treated in all respects “as identical to one Class A share, and Class B shares shall not be subject to discriminatory treatment.”

Expansion reported that Brookfield wants to change the bylaws to pay a lower price for Class B stock. According to the company’s articles of association, Grifols’ (GRFS) Class B holders should be allowed to vote on the change.

Grifols Class A stock fell ~3%, while Class B stock lost ~8% in reaction to the report. Representatives of Brookfield, Grifols (GRFS), and the company’s founding family declined to comment, according to Bloomberg News.