Is Datadog Inc. (DDOG) A Smart Long-Term Buy? Artisan Partners, a high value-added investment management firm, published its ‘Artisan Mid Cap Fund’ first quarter 2021 investor letter – a copy of which can be downloaded here. A return of -2.36% was recorded by its Investor Class: ARTMX, -2.32% by its Advisor Class: APDMX, and -2.30% by its Institutional Class: APHMX, in the fourth quarter of 2020, all below the Russell Midcap® Growth Index that delivered a -0.57% return and the Russell Midcap® Index that was up by 8.14% for the same period. You can view the fund’s top 5 holdings to have a peek at their top bets for 2021.