An idea I've also just started researching, coincidentally. I liked it enough off the bat to take a small starter position despite the valuation, which looks... extended: 24x forward earnings for a business that has been growing about 10%/year. As Jim says, LSE isn't just an 'exchange' operator in the traditional sense. The data and analytics business is about half of earnings, with the other lines together making up the rest. Truly worldwide: they throw out the figure of 44,000 customers in 170 countries and the table of subsidiaries (10.1) runs to eight pages. A lot of recurring subscription revenue.

lseg.com - Lseg annual report

Quick breakdown of LSE's businesses from the AR:

Data & Analytics
Open platform with high-value data and analytics, providing information, insights and workflow to enable customers to execute critical investing, trading and risk decisions.

FTSE Russell
Benchmarks, indices and data solutions with multi-asset capabilities. Our indices help inform asset allocation, support portfolio construction and enable risk and performance analysis.

Risk Intelligence
Suite of solutions to help organisations efficiently navigate risks, avoid reputational damage, reduce fraud and ensure legal and regulatory compliance around the globe.

Capital Markets
Venues and infrastructure to raise or transfer capital through the issuance and secondary markets trading for equities, fixed income and foreign exchange.

Post Trade
Clearing, risk management, capital optimisation and regulatory reporting solutions to help clients manage scarce resources, mitigate
risks and navigate regulation.