By Pushkala Aripaka

(Reuters) -A slowdown in the London Stock Exchange Group's (LSEG.L) recurring revenue growth sent the company's shares down 2% on Thursday despite plans for a share buyback of up to 1 billion pounds ($1.33 billion) after a rise in first-half profit.

LSEG, which operates the London Stock Exchange and supplies data and analytics, has been broadening its offerings to offset competition and meet growing demand fuelled by AI and cloud adoption amid market volatility.

"Despite big swings in capital markets and the global economy, we delivered strong and consistent growth," CEO David Schwimmer told journalists, adding that data demand was growing due to technological advances and a changing regulatory environment.

However, annual subscription value (ASV), which indicates recurring revenue and is closely watched by analysts, rose 5.8% at the end of June on an organic constant currency basis, slowing from 6.4% growth at the end of the first quarter.

Jefferies analysts said ASV growth was likely to dip further to about 5.5% by the end of the current three-month period ending September, due to competitive pressures and changes to customers switching from LSEG's older offerings.

Its shares fell by as much as 5.4% to 9,516 pence but by 1022 GMT had recovered some losses to be down 2%.

LSEG continues to expect organic constant currency growth of 6.5% to 7.5% in 2025 for total income, excluding recoveries, and expects improved margins for the year.

It said total income, excluding recoveries, in the six months ended June was 4.49 billion pounds, up 7.8% on an organic constant currency basis. Analysts were expecting a 7.5% increase, according to a company-compiled consensus.

LSEG, which also raised its interim dividend by about 15%, expects to roll out several products in the second half of the year.

Reuters provides news for LSEG's flagship news and data terminal, Workspace.

($1 = 0.7541 pounds)

(Reporting by Pushkala Aripaka in Bengaluru; Editing by Mrigank Dhaniwala, Nivedita Bhattacharjee and Elaine Hardcastle)