According to bulk deal data available with the NSE, L&T bought over 37.53 lakh shares, or 2.28 per cent stake, worth Rs 367.8 crore, with the average price being Rs 979.96 per scrip.
Meanwhile in a separate transaction, one Rekha N Shah sold 26.84 lakh shares of Mindtree for Rs 263 crore.
L&T has been buying Mindtree shares from the open market for three consecutive days.
It had on Monday bought shares worth about Rs 113 crore.
On Tuesday, L&T purchased 8.43 lakh shares at Rs 979.9 per scrip, translating into a deal size of Rs 82.6 crore.
L&T had signed a deal to buy Cafe Coffee Day owner Siddhartha's 20.32 per cent stake in Mindtree and also placed an order with brokers to pick up another 15 per cent of the company's shares from the open market for about Rs 2,500 crore.
Subsequent to these deals, L&T would make an open offer to buy additional 31 per cent stake.
Shares of Mindtree ended 0.21 per cent higher at Rs 982 on NSE.