Dow Chemical Co. and DuPont Co. are in advanced talks to merge, in a tie-up that would cap off the strongest year ever for takeovers and would come amid a surge of deal activity in the agriculture industry.

The chemical giants, which have a market capitalization of about $60 billion each, could announce a merger in coming days, people familiar with the matter said. It would be followed by a three-way breakup of the combined company, they said, a common approach to mergers and acquisitions of late. Dow’s Chief Executive Andrew Liveris is expected to be executive chairman of the new company, with DuPont Chief ExecutiveEdward Breen keeping that title. A deal has not yet been inked and the talks could fall apart, the people cautioned.

Should it come to fruition, a combination of the companies, each more than a century old, would be one of the biggest in a year marked by big deals. So far, companies have struck some $4.35 trillion of takeovers in 2015, in recent days eclipsing 2007 as the top year on record for deals, according to Dealogic.

It would create a giant with more than $90 billion in combined sales and strong positions in everything from plastics to industrial chemicals and agriculture.

Under pressure from shareholders to slim down and focus on faster-growing units, both companies have been restructuring their businesses by shedding some of the products that made them famous.