A Microsoft audit is a negotiation that starts with the vendor's number

Defence means building your own number first, scoping the data request before anything leaves the network, and treating every claim as an opening position rather than a finding. Most reviews are triggered by spend, migration, or merger signals rather than random selection, which means the letter is predictable and the preparation can start before it arrives.

Prepared by Redress Compliance · August 10, 2026 · Microsoft advisory. Based on 60 to 80 Microsoft audits and SAM engagements defended, 2024 to 2025.

• A flat or falling renewal while headcount grows, which reads as under licensing from the outside regardless of what actually happened inside the estate.
• A large cloud migration, since moving workloads to a hyperscaler or a rival platform invites a licence position check on what was left behind.
• An acquisition or merger, because combined estates rarely reconcile cleanly against an existing agreement and the mismatch is visible in the purchase record.
• Lapsed support coverage, where gaps raise upgrade and mobility rights questions that are cheap to ask and expensive to answer late.
• Read the product terms before you respond, not after, because they define the rights you are being measured against and the measurement has already started.

Two exposures produce most of the number, and they behave differently.

The classic one is server core counting and virtualization, where a raw inventory export counts capability rather than entitlement and the rules about how cores are counted across a virtual estate are precisely the rules a generic discovery tool does not apply.

That is where the 20 to 40 percent overstatement concentrates alongside unassigned seats, and it is correctable with evidence rather than argument: a defensible core count built from your own configuration records, produced before the export is shared rather than after the claim is written.

The modern one is cloud sprawl, which drove 30 to 50 percent of the disputed amount in our file and which nobody owns in most organisations.

Subscription add ons accumulate outside any procurement gate, consumption grows without a licensing consequence anyone records, and the estate that gets measured is therefore larger than the estate anyone deliberately bought.

Reconciling that before submission is the single highest return preparation available, because unlike the core count it cannot be argued down after the fact: the seats existed and were assigned. The discipline that ties both together is sequencing.

Verify your own position before sharing any inventory export, because a document sent is a document interpreted. Scope the data request against the contractual clause, since an out of scope request can be declined while an out of scope submission cannot be recalled.

And run the phases on your calendar rather than the reviewer's, because a compressed timeline produces concessions that a normal one does not. The cross vendor sequence sits with Vendor Shield.

Across roughly 60 to 80 Microsoft audits and SAM engagements we defended between 2024 and 2025, the opening compliance claim was almost never the number the client actually owed:

Three patterns recurred: the first compliance statement overstating the gap by 20 to 40 percent, usually on server cores and unassigned seats; around one review in three arriving dressed as a free engagement while the data fed straight back to the licensing desk.

And cloud sprawl driving 30 to 50 percent of the disputed amount.

The buyer side move is to build your own number before the review starts, treat both routes with identical discipline, verify every export against the contractual scope before it leaves the network, and run the phases on your own calendar. Defend first, concede last.

The wider library sits in the Microsoft practice.

What triggers a Microsoft software audit?

A data signal rather than a random draw. The licensing desk watches purchase history, cloud spend, and contract anniversaries. The common triggers are a flat or falling renewal while headcount grows, a large cloud migration, an acquisition or merger, and lapsed support coverage.

Knowing them lets preparation start before the letter arrives.

How does a SAM engagement differ from a formal audit?

A formal audit is a contractual right exercised by an independent firm under the audit clause, with the data you owe defined by that clause. A SAM engagement is an invitation, often free, run by the vendor or a partner and framed as optimisation.

Both can end with a number you are asked to pay, and both feed the same licensing desk.

Why is the friendly framing the bigger risk?

Because it lowers response discipline rather than stakes. A free engagement feels low consequence, so teams export raw inventory and hand it over without review, and that data then becomes the baseline for any claim.

The correct handling is identical to a formal audit: verify your position first, scope every request, and share nothing unreviewed.

How accurate is the opening compliance claim?

In most cases we defended it overstated the gap by 20 to 40 percent, concentrated on server core counts and unassigned seats.

It is an opening position rather than a finding, and it behaves like one, which means the response has to be your own defensible number rather than an explanation of why theirs feels high.

Where does the disputed amount come from?

Increasingly from cloud sprawl, which drove 30 to 50 percent of the disputed amount in our file through unmanaged subscription add ons and consumption that nobody reconciles.

The classic exposure, server core counting across a virtual estate, remains the other major source, and it is the one that responds best to evidence.

Should we share our inventory export?

Not before verifying your own position against it. A raw export counts capability rather than entitlement, particularly across a virtual estate, and once shared it is interpreted by someone whose role is to find a gap.

Scope the request against the contractual clause first, because an out of scope request can be declined while a submission cannot be recalled.

Whose timeline should the review run on?

Yours, phase by phase. A compressed timeline produces concessions that a normal one does not, and the reviewer's schedule is built for the reviewer's convenience rather than for the accuracy of the result.

Running the phases deliberately is one of the few controls available that costs nothing and changes the number.