**Document Title:**

This document appears to be an insurance endorsement or amendment, specifically related to Zurich Insurance Company and American Guarantee and Liability Insurance Company.

**Key Information:**

- **Named Insured:** International Business Machines Corp.
- **Effective Date of Policy:** 5-21-76
- **Endorsement Date:** 5-21-77
- **Additional Premium:** $3600
- **Premium Breakdown:**
  - Payable 5-21-76: $3000
  - Payable 5-21-77: $3600
  - Payable 5-21-78: To be determined
- **Total Premium:** $3600 (U.S.A.: $3485, Canada: $115)
- **Other Terms and Conditions Remain Unchanged**

**endorsement text:**

In consideration of an Additional Premium of $3600, it is agreed that Item 4 (C) Premium is amended to read:

Payable 5-21-76: $3000
* Payable 5-21-77: $3600
5-21-78: To be Determined

* U.S.A: $3485
Canada: $115
Total: $3600

All other terms and conditions remain unchanged.

**Signatures:**

- Zurich Insurance Company
- American Guarantee and Liability Insurance Company

**Counter-signed by:**

[Signature present but not legible]

**Authorized agent:**

[Signature present but not legible]