MADRID, Sept 20 (Reuters) - Three investment funds with

holdings in Spanish drugmaker Grifols have teamed up

to ask to fill a vacant seat on the company's board, they said

in a statement late on Thursday.

Flat Footed LLC, along with Mason Capital Management LLC and

Sachem Head Capital Management LP, which hold a combined 7.72%

stake in Grifols, picked Paul Herendeen, a former senior

executive at other large pharmaceutical companies, to be their

representative on the company's board, the statement said.

They said Grifols, which produces plasma-based medicines,

had "an attractive growth profile" and its shares were

undervalued and they wanted to make sure any takeover offer

would include "a price that is fair for all shareholders".

Grifols lost a third of its market value in January when

short-seller fund Gotham City Research started releasing several

reports accusing Grifols of overstating earnings and

understating debt. Following the reports Grifols announced

governance changes and revised its reported leverage higher.

The Grifols family, which holds a stake of around 30% in the

company, and Canadian fund Brookfield agreed in July to

evaluate a possible joint takeover bid for Grifols shares with

the intent to delist it.

Grifols earlier this month said the founding family and

Brookfield were in the process of due diligence and had not made

any decision on an offer yet.

(Reporting by Natalia Siniawski; Editing by Emelia

Sithole-Matarise)