## Facts

- Gerber Truck Service, Inc. acquired a trucking operation that employed three union drivers covered by Central States multiemployer benefit funds.
- Gerber employed other nonunion drivers and sought to keep benefit coverage only for the three union drivers while avoiding union wages and benefits for other employees.
- Gerber and the union signed a written collective bargaining agreement and a written participation agreement that, by their terms, required contributions for all covered employees/drivers in the bargaining unit.
- At the same time, Gerber and the union representative allegedly made an oral side understanding that contributions and coverage would be limited to the three union drivers.
- The written documents were submitted to the funds, and for a period contributions were made only for the three union drivers consistent with the alleged oral understanding.
- After the three union drivers retired, Gerber stopped paying contributions; an audit later revealed additional employees who appeared covered under the written terms.
- The funds credited covered employment for those additional employees and demanded retroactive contributions based on the written agreements; Gerber refused, relying on the alleged oral limitation.
- The district court enforced the oral understanding against the funds and limited liability to contributions for the three union drivers.

## Issues

1. Under ERISA § 515, may an employer defeat or limit a multiemployer fund’s contribution-collection action by invoking oral side agreements or practices with the union that contradict unambiguous written contribution obligations?
2. To what extent does ERISA § 515 restrict contract defenses in fund collection suits to those consistent with enforcing the written terms of the plan or collectively bargained agreement?

## Decision

- The Seventh Circuit (en banc) reversed.
- The court held that ERISA § 515 allows a multiemployer plan to enforce written contribution obligations according to their terms, so long as enforcement is not inconsistent with law.
- Oral side agreements, informal understandings, or course-of-performance arrangements between employer and union cannot be used to defeat the fund’s claims grounded in the written instruments submitted to the fund.
- Gerber was obligated to pay contributions for all employees covered by the written agreements, notwithstanding the alleged oral limitation.

## Legal Principles

- ERISA § 515 measures an employer’s contribution duty by the written “terms of the plan” or the written “terms of a collectively bargained agreement,” limiting the defenses available in collection actions.
- Multiemployer funds may rely on the plain terms of written contribution documents and are not bound by employer-union side deals that contradict those writings.
- Defenses that would rewrite or modify clear written obligations (including oral modification, course-of-dealing limitations, and inducement-type defenses) generally are unavailable against a fund in a § 515 action.
- Narrow defenses may remain where they negate the existence of an obligation under the writing (e.g., certain formation defects or illegality), but not where the employer admits execution of a facially valid written promise and seeks to reduce it by extrinsic agreements.
- The rule supports administrative certainty and protects plan participants by allowing funds to calculate contributions and benefits based on the written documents they receive.

## Conclusion

ERISA § 515 permits multiemployer benefit funds to collect contributions based on the unambiguous written terms of contribution agreements, and an employer cannot avoid those obligations by asserting an oral side agreement or practice with the union that limits what the writings require.


Cent. States, Se. & Sw. Areas Pension Fund v. Gerber Truck Serv., Inc., 870 F.2d 1148 (7th Cir. 1989) (en banc)