VANCOUVER -- Aurora Cannabis Inc.'s all-stock hostile takeover bid of medical marijuana company CanniMed Therapeutics has the backing of a Toronto-based investment manager, two Saskatchewan venture capital funds, and an investment fund also based in the prairie province, according to regulatory filings.

Shares of Aurora (TSX:ACB) were up as much as 16 per cent in late afternoon trading after the Vancouver-headquartered marijuana producer officially launched its bid on Friday, while shares of CanniMed (TSX:CMED) slipped as much as 3 per cent by early afternoon in Toronto.

Aurora signed lock-up agreements with four CanniMed shareholders -- which comprise 38 per cent of outstanding shares -- on Nov. 13 to support its unsolicited takeover bid, one day before it made its proposal public, according to a circular outlining its offer.

These four institutional shareholders are Golden Opportunities Fund Inc. with a 17.33 per cent stake, Saskworks Venture Fund Inc. with 8.42 per cent, Apex Investment Limited Partnership with 3.48 per cent and Toronto's Vantage Asset Management holding 8.71 per cent, filings show.

Aurora formally launched its takeover bid with a newspaper ad and circular detailing its offer to acquire all issued and outstanding shares for up to $24 each, with one of its conditions being that CanniMed abandon its own proposed acquisition of Newstrike Resources Ltd. (TSXV:HIP)

CanniMed said Friday that Aurora's acquisition does not make sense for its shareholders, but the combination with the Tragically Hip-backed Newstrike is poised to deliver significant shareholder value.