ZURICH, April 8 (Reuters) - Shareholder pressure is growing on insurer Baloise to change its voting rules, with influential proxy advisor Glass Lewis backing one investor's bid to remove a 2% ceiling on voting rights, saying it would make the Swiss group more attractive.

Baloise shareholders have no more than 2% of votes, irrespective of how big their stake is, meaning that major investors like BlackRock or UBS cannot fully bring their weight to bear on decision-making.

Investor zCapital is seeking to change that. In its view, lifting the curbs would make Baloise more attractive for long-term financial investors. Shareholders can vote on the proposal, which Glass Lewis endorsed, on April 26.

"We believe that voting rights restrictions inhibit shareholder democracy and can reduce the attractiveness of a company for a potential takeover as well as to potential strategic partners, which can lead to an undervaluation of a company's shares," Glass Lewis said in its assessment of the proposal, which it shared with Reuters on Monday.

The Baloise board has recommended rejecting the proposal, having argued that lifting voting rights curbs was not in the long-term interests of the firm and most of its shareholders.

Curbs on voting rights can be used to protect companies from unwanted takeover attempts.

Basel-based Baloise wants in 2025 to submit its own proposals to alter restrictions on voting rights.

Glass Lewis also backed zCapital on a second contentious proposal. The asset manager has recommended reducing the threshold for reaching a qualified voting majority at Baloise to two-thirds from three-quarters at present.

Baloise did not immediately reply to a request for comment. (Reporting by Oliver Hirt Editing by Tomasz Janowski)