Download of RMS_sharing 1.3.8 for Mac was available from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The software relates to Security Tools. Please check the Mac app with an antivirus before launch as it is downloaded from the developer's website, and we cannot ensure that it is safe. The actual developer of this free Mac application is Microsoft.
From the developer:
RMS sharing app enables you to view protected files that others have shared with you (.ppdf, .ptxt, .pxml, .pjpg, .pjpeg, .ppng, .ptiff, .pgif, .pbmp, and .pfile file extensions).
NOTE: You need to have RMS for individuals or an RMS enabled Office 365 account to use Microsoft Rights Management sharing application (RMS sharing app). You can register at https://portal.aadrm.com. You cannot use Microsoft Account (Live, Hotmail or Outlook.
You may want to check out more Mac applications, such as RMS sharing, which might be similar to RMS_sharing.