** Shares of marketing platform AppLovin APP.O rise 4.3% to $272.98

** Stock slumped over 20% in the prior session after Muddy Waters Research disclosed short position

** Muddy Waters is latest to short APP after Fuzzy Panda Research and Culper Research revealed short positions in February

** Analysts at Loop Capital and Wells Fargo dispute Muddy Waters' claims

** Wells Fargo's Alec Brondolo says APP's e-commerce incrementality is strong at between 55% and 60% new customers, versus Muddy Waters' claim of a more than 50% retargeting mix

** Loop Capital says short report's claims of faulty conversions and fraud "easily disproved" by analysts' discussions with performance marketers and measurement companies

** "We would be aggressive buyers on weakness ahead of a major expansion cycle now underway... AppLovin remains our top pick for the year" - Loop Capital

** Loop Capital reiterates "buy" rating and $650 price target on APP, while Wells Fargo maintains "overweight" rating and $538 price target

** Short interest in stock at 3.8% of public float, according to data compiled by LSEG

** APP says it has retained law firm to investigate recent short seller activity

** Twenty of 26 brokerages rate APP "buy" or higher; the median PT is $550

** APP has dropped 15.7% YTD

(Reporting by Lisa Pauline Mattackal)

((LisaPauline.Mattackal@thomsonreuters.com;))