The Jamaica Stock Exchange (JSE) is set to lose its largest company, and with it more than a tenth of the Main Market’s value.

Scotia Group Jamaica (SGJ) will be delisted after 57 years if the Supreme Court sanctions a $75-a-share buyout by Scotiabank Caribbean Holdings at a hearing on October 30. Minority shareholders approved the offer on Wednesday.

SGJ was valued at $226.75 billion on September 30, or 10.55 per cent of the Main Market. Those figures imply a total market value of about $2.15 trillion, falling to roughly $1.92 trillion once the bank is removed.

The index changes mechanically. With SGJ gone, the weight of every remaining Main Market stock rises by about 12 per cent in relative terms. A company that made up 5 per cent of the market would account for about 5.6 per cent. The largest remaining stocks gain the most influence over daily index moves.

Sector balance shifts too. SGJ is the exchange’s most profitable company, so its exit lowers the aggregate earnings of listed firms and reduces the banking sector’s share of the index.

The effect on trading may be smaller than the headline weight suggests. Scotiabank already owned the majority of SGJ, so only the minority stake changed hands on the market. That stake is being bought for a reported $63.50 billion to $64 billion. How much liquidity leaves depends on SGJ’s share of daily turnover.

Funds that track or benchmark against the JSE indices will have to rebalance. Fee income for the exchange also falls with the loss of a large issuer.

The exit comes as the exchange seeks new listings. No company of comparable size has announced plans to list.

The delisting date depends on the court’s decision on October 30.