Re-seller deal with SAP could mean growth (see link). BL fills a gap in SAP's system and I can see a case for them being bought outright.
https://www.blackline.com/about/press-releases/2018/blackline-announces-reseller-agreement-with-sap
https://www.blackline.com/about/press-releases/2018/blackline-announces-reseller-agreement-with-sap