What Is a Commercial Lease? Key Terms, Types, and What to Watch For
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Lextract extracted 126 fields from Bicara Therapeutics' office expansion amendment: dual-premises RSF calculation, blended rent, and separate commencement dates.
By Angel Campa, Founder · Updated March 2026
Location
Boston, MA
Size
9,300 RSF
Annual Rent
$558K/yr
Term
48 months
Tenant
Bicara Therapeutics
Landlord
ARE-MA Region No. 54
This expansion amendment doubles the tenant's footprint from 4,600 to 9,300 RSF. Extracting the correct square footage requires distinguishing between the original premises, the expansion space, and the combined total. Rent is stated per-square-foot for the expansion space only, requiring calculation of the blended total rent.
Lextract correctly identified the expansion space (4,654 RSF) and the original premises (4,646 RSF), computed the combined 9,300 RSF total, and extracted the blended annual rent. The per-RSF rate for the expansion space was extracted and the effective commencement date for the expansion was separately tracked.
126
Fields Extracted
5-15 minutes
Extraction Time
| Field | Extracted Value | Why It Matters |
|---|---|---|
| Original Premises | 4,646 RSF | Required to compute combined square footage |
| Expansion Space | 4,654 RSF | New premises added by this amendment |
| Total RSF | 9,300 RSF | Combined premises post-expansion |
| Annual Rent (expansion) | $120/RSF | Market rate for expansion space, above original space rate |
| Expansion Commencement | January 1, 2023 | Separate effective date for expanded space |
| Tenant Improvement Allowance | $60/RSF on expansion | TI applies to expansion space only |
Lextract extracts each premises component separately, capturing the RSF, rent, and commencement date for each component, then computes the total combined premises and a weighted average rent.
The most critical fields are: combined total RSF, per-RSF rent for the expansion space, expansion commencement date, updated pro rata share, and any changes to the TI allowance or security deposit.
A commercial lease is a legally binding contract between a landlord and a business tenant. Learn the key terms, lease types, and critical clauses before you sign.
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