This is the outline of a leaf. Leaves were used to wrap foodstuffs for storage. The template may have been a leaf from a sal tree. However, the absence of detail indicates that the plant is not important. The symbol is an ideograph for a wrapper. It is the verb to keep, to store up, or to stock.
Illustrative Text Reference:
Harappa: Seal: H-10 a: Jagat Pati Joshi and Asko Parpola, 1987: Corpus of Indus Seals and Inscriptions: Volume 1: Page 167: Collections in India: Suomalainen Tiedeakatemia.
Comment:
In inscription H-10, this symbol is repeated. There is literally more than one item in storage. Hence, repetition of Mahadevan's sign number 323 is an ideograph for the verb to hoard.
Image Credit:
Indus Script Sign Number 323: Sign List of the Indus Script: Iravatham Mahadevan, 1977: The Indus Script: Texts, Concordance and Tables: The Director General Archaeological Survey of India.