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April 19 (Reuters) - Qualcomm Inc, the largest maker of chips used in smartphones, reported higher-than-expected quarterly adjusted profit and revenue, helping allay concerns about the company's patent-licensing business.
The company's shares were up 2.4 percent at $53.85 in aftermarket trading on Wednesday.
Qualcomm forecast current-quarter adjusted profit of $0.90-$1.15 per share and revenue of $5.3 billion-$6.1 billion.
Analysts on average were expecting a profit of $1.09 per share and revenue of $5.94 billion, according to Thomson Reuters I/B/E/S.
Qualcomm's patent-licensing practices have come under increasing scrutiny from governments across the world, as well as its key customers.
Apple Inc sued the chipmaker in January, accusing Qualcomm of overcharging for its chips and refusing to pay some $1 billion in promised rebates.
Qualcomm fired back at the iPhone maker last week, saying Apple had breached agreements with the firm.
In the counterclaim, Qualcomm also said Apple and other contract manufacturers were holding back licensing payments for the use of the chipmaker's products in Apple's devices.
The company warned on Wednesday that it was unclear whether Apple's contract manufacturers would underpay royalties owed in the third quarter.
Revenue fell 9.6 pct to $5.02 billion in the second quarter ended March 26.
The quarter included a $974 million reduction to revenue, or 48 cents per share, related to the BlackBerry arbitration decision, Qualcomm said on Wednesday.
On an adjusted basis, Qualcomm reported revenue of $5.99 billion, beating analysts' average estimate of $5.89 billion.
Net income attributable to the company fell to $749 million, or 50 cents per share, in the second quarter ended March 31, from $1.16 billion, or 78 cents per share, a year earlier. (bit.ly/2ot17st)
Excluding items, Qualcomm earned $1.34 per share, above the average analysts' estimate of $1.19.
The litigation has weighed on Qualcomm's shares, which are down about 19 percent this year through Wednesday's close. The stock is the worst performer this year on the Philadelphia semiconductor index, which has gained about 8 percent. (Reporting by Narottam Medhora in Bengaluru; Editing by Sriraj Kalluvila)