Blog · Published 2026-10-18
CIM vs teaser vs IOI: what each document is and what to do with it.
A teaser is a short, usually anonymous summary a seller's side sends to find interested buyers. A CIM is the longer memorandum a buyer receives, usually after signing an NDA. An IOI is the buyer's own non-binding indication of interest, written back to the seller. The first two are the seller's documents; the IOI is yours.
Side by side
Process details vary by deal, and small deals often skip or merge steps. This is the usual order and purpose.
| Document | Written by | Usually arrives | What it holds | What a buyer does with it |
|---|---|---|---|---|
| Teaser | Seller or broker | First, often before an NDA | A short anonymous description of the business and why it is for sale. | Decide whether to ask for more. There is too little here to test any claim. |
| CIM | Seller or broker | After the NDA | The seller's detailed account of the business, with financial summaries. | Test it against the financial statements and tax returns; this is the main document to cross-check. |
| IOI | Buyer | After reading the CIM | A non-binding statement that you are interested, often with a value range and conditions. | Write it only on claims you have checked. What you assume in the IOI is what you will have to defend later. |
| LOI | Buyer, negotiated with seller | After the IOI or in place of it | Proposed price and terms, and the conditions for diligence and closing. | Confirm the open items from your CIM review before you sign it. |
Why the order matters for diligence
The CIM is written to sell. It is not false by default, but it is the one document in the process whose author gains from a reading that is favorable. That is why the checks that matter most compare it with documents the seller did not write for the sale: financial statements, tax returns and contracts.
An IOI sits between the CIM and the LOI. If you put a range in it, the range rests on the CIM's figures. A first pass on the CIM before the IOI shows which of those figures hold, so you do not put a number in writing that depends on one that does not. The checklist for that pass is the CIM review template.
What software can do with each
- Teaser: very little. It has too little in it to cross-check. Read it yourself.
- CIM: the main input. Deal OS reads it with the financials and tax return and reports contradictions and gaps with page citations. The CIM Pass page shows how to run one.
- IOI and LOI: your documents, which you and your advisors write. The output of the CIM review feeds the open items you attach to them.
Worked example from the sample brief
Why the CIM is the document to cross-check, from the sample brief (a synthetic deal):
- A claim contradicted by the document's own table. The CIM says on page 8 that no customer is more than 15% of revenue. Page 9 lists the top account (Northgate Property Group) at $1,366,000 against $6.21M of revenue, which the brief computes as 22.0%. The brief shows both passages word for word, each with its page, and marks the page 8 statement as false on the CIM's own numbers.
- A headline figure that two documents state differently. Trailing twelve month revenue is $6.21M on page 6 of the CIM and $5.95M as gross receipts on the tax return. The brief shows the $260K gap side by side and says to reconcile it before applying any multiple.
- A definition that changes what a number means. Page 7 says about 78% of revenue is recurring. Page 22 defines recurring as all revenue from accounts with an active inspection agreement, including repair and call-out work. The brief flags the two passages as inconsistent and asks for a revenue cut that separates fixed inspection billings from variable work.
- Add-backs sorted by whether they are likely to survive. The seller presents adjusted EBITDA of $1.42M. The brief itemizes the add-backs and rates each one; $90K of them are rated questionable or unlikely, which gives $1.33M that holds up on the documents. The arithmetic is computed, and the ratings are a first judgment for a human to confirm.
- A statement the documents do not support, thrown out. While drafting, the model proposed that the company has no outstanding litigation. No passage says so, so the verifier discarded it and the brief lists it in a verification log, with a request for a 10-year litigation history instead.
The example is Sentinel Fire & Safety, Inc., a synthetic company built to show the product. Nothing in it describes a real business, and the same output shape applies to a real data room. See the whole thing at /sample-brief.
See it on a deal.
Open a real brief on a synthetic deal without an account, or check how a single deal is priced.
