The McGill's Buses owner is the second investor to buy shares in the club in recent days.
Accountant and pension fund manager David Somers has bought his first stake in Rangers, six months after becoming the club's non-executive chairman.
Mr Easdale bought a further 57,043 ordinary shares at a cost of 23p a share on May 1.
He now owns three million shares in the new Rangers PLC, and holds voting rights over a further 14million shares, representing 22% of the company.
He is thought to have paid around £13,000 for the shares, which means he remains the single biggest shareholder, with control over 26% of the club.