* Posted 17 percent drop in profit in Q3
* New 2 billion euro share buy-back program
* Hurricanes and earthquakes have rocked industry (Adds details from CFO call, background)
FRANKFURT, Nov 10 (Reuters) - Allianz has slightly downgraded its profit outlook for the full year after increased claims from natural disasters in North America, the German insurance giant's finance chief said.
Hurricanes Harvey, Irma and Maria, two earthquakes in Mexico, and fires in California have prompted the insurer to lower its forecast for the year "by a smidgen," Allianz Chief Financial Officer Dieter Wemmer told journalists on Friday.
Allianz forecast operating profit in the "upper half" of its target range of between 10.3 billion euros and 11.3 billion euros on Thursday. It had previously said that profit would be "near the upper end" of that range.
Allianz posted a 17 percent fall in net profit in the third quarter to 1.6 billion euros ($1.9 billion), with the catastrophes costing it more than 500 million euros.
Analysts at KBW said in a note that the hit to Allianz was "actually not too bad in a global context" after Munich Re this week posted a big third-quarter loss, while Hannover Re reported a profit after selling its nearly 1 billion euro stock portfolio.
"Third quarter results were robust, given the massive natural catastrophe events that impacted our property and casualty segment," Oliver Baete, Allianz's CEO, said.
The series of natural disasters has rocked the insurance industry after years of muted losses, compounding pressure from low prices caused by fierce competition and low interest rates.
Insured losses from the three big hurricanes have cost the industry around $100 billion, Munich Re said, that would exceed industry-wide losses of about $74 billion caused by Katrina, the hurricane that devastated New Orleans in 2005.
In a sign of their toll on profit, Allianz said its combined ratio, a closely-watched measure of expenses to premium income, rose to 96.9 percent from 93.5 percent for its property and casualty division.
Allianzs asset management business showed signs of strength, with third-party assets under management rising by 7 billion euros to 1.4 trillion euros at the end of the third quarter compared to the end of the second quarter.
But lower performance fees dragged on operating profit at the unit, which includes bond fund manager PIMCO.
Allianz also announced a 2 billion euro ($2.3 billion) share buy-back program. Shares in the insurer were 1 percent higher at 202.30 euros at 1209 GMT. ($1 = 0.8589 euros) (Reporting by Tom Sims; Editing by Arno Schuetze/Toby Chopra/Alexander Smith)