Wesfarmers has bolstered its chances of taking over Australian Pharmaceutical Industries after buying a 19.3 per cent stake.
The retail giant on Thursday took its first stake in the Priceline and Soul Pattinson chemist operator and is competing with rival suitor and pharmacy operator Sigma Healthcare.
Wesfarmers' move helps its bid as the company will not vote in favour of Sigma's offer.
The former has a fixed offer of $1.55 per share. Sigma has a live offer, which was worth $1.51 per share (based on Wednesday's closing price) as it comprises 35 cents and 2.05 Sigma shares for each API share.
The healthcare company says a merged entity can save at least $45 million per year.
Wesfarmers bought the shares from Washington H Soul Pattinson for $1.38 each as outlined in the former's initial proposal in July.
This makes the retail giant the top shareholder in API.
He said there were opportunities to expand the product range, improve online shopping and the supply chain.
In September, API said the Sigma proposal was likely to be more favourable than the Wesfarmers one.
Both suitors have been allowed to examine the financials of their takeover target.
Australian Pharmaceutical Industries shares were higher by 1.5 per cent to $1.52 at 1302 AEDT.
Wesfarmers shares were up 1.07 per cent to $54.65.
Sigma shares were even at 57 cents.