SAO PAULO (Reuters) - Shares in Brazilian software maker TOTVS jumped 6.6% on Thursday after proxy adviser Institutional Shareholder Services said shareholders in takeover target Linx SA LINX3.SA should vote against a rival acquisition proposal from card processor StoneCo Ltd STNE.O. TOTVS SA TOTS3.SA and StoneCo have been in a bidding war since August to take over Linx. The TOTVS share increase will make its own buyout proposal for Linx more attractive to the latter’s shareholders because it is mostly a stock deal with a minor portion in cash. ISS said Linx has not given a strategic rationale to justify the deal, adding that the company"s shares had fallen more than 20% between Jan. 1 and the announcement of the proposed deal in August. Linx shares have risen 3.3% year-to-date, while Brazil"s benchmark stock index .BVSP has fallen 15.4%. “The offer does not represent a premium to prices before COVID-19 and appears to be in the trading range of the stock during 2019,” ISS wrote. StoneCo offered a premium of 34.9% over the price prior to the takeover announcement. ISS compares Linx multiples with companies such as TOTVS, Sinqia and PagSeguro Digital Ltd PAGS.N and says StoneCo"s offer price implies a discount to peers. Another proxy advisory firm, Glass Lewis, recommended shareholders vote in favor of the StoneCo offer. “The strategically sound arrangement with StoneCo provides the most certain and compelling terms available following a competitive and highly public sale process,” it said in a note. Glass Lewis added that TOTVS’ offer is lower in value and implies higher risks in terms of antitrust approval. Still, it said Linx should keep up talks with TOTVS in case a deal with StoneCo fails. Shareholders had been scheduled to vote on the StoneCo deal on Nov. 17. A Linx shareholder on Thursday asked Brazil’s securities regulator CVM to postpone the shareholder meeting to vote on the StoneCo offer, CVM confirmed.