Exfo says Germain Lamonde is now offering US$6.25 per share, up from an earlier proposal of US$6 per share.
The company also says it and Lamonde have secured the support of minority shareholders holding 14.75 per cent of its issued and outstanding subordinate voting shares, other than those held directly or indirectly by Germain Lamonde and Philippe Morin.
A special meeting of shareholders to vote on the offer is set for Friday.
Last week, proxy advisory firm Glass Lewis said minority shareholders should vote against the deal, however Institutional Shareholder Services has recommended shareholders accept the offer.
Shares in Exfo, which makes test, monitoring and analytics equipment for the communications industry, closed at C$7.14 on the Toronto Stock Exchange on Friday.
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