New Delhi is seeking to raise as much as $11 billion by selling stakes in state-run firms this year.
While LIC is a frequent back up for government sales, the sum it bought on Monday, amid a stock market rout, is likely to raise questions over the future of the sell-off programme.
The Indian government sold 10 percent of Indian Oil, raising around $1.4 billion.
Officials at LIC, whose stake has risen to 11.11 per cent in Indian Oil from 2.52 per cent according to Tuesday's filing after market hours to the Bombay Stock Exchange, did not immediately respond to requests for comment.