What should the denominator in my pro-rata share be?

Your lease defines the denominator. It is usually the total rentable area of the building, the total rentable area of the applicable CAM pool (which may be a portion of the building), or the total occupied rentable area. The distinction between total and occupied area is critical: using occupied area inflates each tenant's share when the building has vacancies.

Is my pro-rata share fixed or does it change annually?

It depends on your lease. Some leases specify a fixed percentage for the entire lease term. Others recalculate annually based on the total occupied square footage. If your lease uses a fixed percentage, the landlord cannot unilaterally apply a different figure. If it recalculates annually, request the square footage schedule used each year.

What happens if my leased square footage was measured incorrectly?

Your pro-rata share numerator is based on the rentable square footage of your space. If that figure is wrong, every year's CAM allocation is also wrong. You can request a re-measurement under the lease's audit rights clause. Some tenants discover that a re-measurement both reduces their base rent and corrects their pro-rata share.

Can the pro-rata share be different for different CAM expense categories?

Yes. Some leases specify separate pro-rata shares for utilities, parking, security, and other cost pools. A single blanket pro-rata share applied to all categories can either overcharge or undercharge depending on which categories use a different allocation basis. CAMAudit checks each category against the lease's allocation rules.

Math-Based Rule

Pro-Rata Share Error: How CAMAudit Detects This Overcharge

Even a 1% error in your pro-rata share fraction compounds across every line item in your CAM statement. On a $100,000 total CAM bill, that's $1,000 in overcharges every year from a single number.

How CAMAudit Detects This

CAMAudit extracts your pro-rata share percentage and its components from your lease: your leased square footage (numerator) and the applicable building or project square footage (denominator). It also extracts whether the lease uses a fixed percentage, a recalculated annual percentage, or a custom allocation formula.

The tool then compares the pro-rata share used in your reconciliation against the figure computed from the lease definition. If the landlord applied a different percentage, CAMAudit flags the discrepancy and calculates the overcharge by multiplying the variance by the total CAM pool.

CAMAudit also checks whether the denominator definition matches common manipulation patterns: landlords sometimes exclude vacant space from the denominator, shrinking it and inflating each remaining tenant's share. Your lease should specify whether the denominator is fixed or adjusts for occupancy.

Real-World Example

A tenant leased 4,800 sq ft in a 60,000 sq ft building. Their lease specified a fixed pro-rata share of 8.0% (4,800 / 60,000). The reconciliation applied 10.2%, noting the building had 47,100 sq ft of occupied space. The landlord was excluding vacant units from the denominator. CAMAudit flagged the variance: on a $185,000 CAM pool, the tenant was billed $18,870 instead of the correct $14,800, a $4,070 overcharge for that year alone.

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Find My Overcharges

Pro-Rata Share Error: How CAMAudit Detects This Overcharge

Even a 1% error in your pro-rata share fraction compounds across every line item in your CAM statement. On a $100,000 total CAM bill, that's $1,000 in overcharges every year from a single number.

How CAMAudit Detects This

Real-World Example

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Upload your lease. CAMAudit runs 13 detection rules in under 5 minutes.

Find My Overcharges

See a sample report first

Frequently asked questions

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Find overcharges in your CAM reconciliation. Most audits complete in under 5 minutes.

Find My Overcharges See a sample report first