As of June 9, 2021, when a filer is using an internet browser other than Internet Explorer, EDGARLink Online will allow that filer to attach multiple documents at once to EDGAR submissions. Filers using Internet Explorer must continue attaching documents to EDGAR submissions one at a time.
For questions or further details, contact Filer Support at (202) 551-8900 and choose option 3 when prompted. Filer Support is available Monday through Friday (except federal holidays), 9:00 a.m. to 5:30 p.m. ET.
Sources:
EDGARLink Online Document Attachment Capabilities (sec.gov)