Microsoft, a participant in the sales engine's $60m series D round, has come back for a series E round led by Polaris Partners.

InsideSales, the US-based operator of an online sales platform, completed a $50m series E round on Wednesday led by venture capital firm Polaris Partners that included software supplier Microsoft.

Ireland Strategic Investment Fund (ISIF), an $8.1bn vehicle managed by the Irish government, also invested, as did QuestMark Partners, Kleiner Perkins Caufield & Byers (KPCB), Hummer Winblad, US Venture Partners (USVP), Epic Ventures and Zetta Ventures.

InsideSales has developed an artificial intelligence (AI)-equipped sales engine called Neuralytics that offers features such…