The Indus Dictionary Project
This is the sign for the concept of sharing with the addition of the outline of an area. Hence, it is the noun public space.
Harappa: Tablet in bas-relief: H-1115 A: Asko Parpola, B. M. Pande, and Petteri Koskikallio, 2010: Corpus of Indus Seals and Inscriptions: Volume 3,1: Page 155: New material, untraced objects, and collections outside India and Pakistan: Suomalainen Tiedeakatemia.
Mohenjo-daro: Seal: M-1134 a: Sayid Ghulam Mustafa Shah and Asko Parpola, 1991: Corpus of Indus Seals and Inscriptions: Volume 2: Page 125: Collections in Pakistan: Suomalainen Tiedeakatemia.
Please note that the rhinoceros motif on seal impression M-1134 faces left. This indicates that inscription M-1134 should be read from left to right.
Indus Script Sign Number 2651: List of Sign Variants: Iravatham Mahadevan, 1977: The Indus Script: Texts, Concordance and Tables: The Director General Archaeological Survey of India.