The Australian Competition and Consumer Commission designed the undertakings to ensure Alinta did not use its management and part ownership of the infrastructure to discriminate against other pipeline users.

The ACCC filed proceedings against Alinta in September last year after determining those undertakings had not been met.

The Federal Court ruled yesterday that Alinta had breached the undertakings by having a member of its staff involved in commercial negotiations with gas shippers about use of the pipeline.

The Federal Court found that from January 2006 until October 2006, a member of Alinta staff was involved in commercial negotiations between DBNGP Holdings and gas shippers.

Alinta's conduct in transferring that staff member into that position and permitting her to remain there when the company knew she was involved in commercial negotiations with gas shippers was a breach of the undertakings Alinta had given.

"The undertakings were put in place to ensure that Alinta's competitors were not negotiating with Alinta staff about their use of the pipeline," ACCC chairman Graeme Samuel said yesterday.

"The situation that arose was unacceptable and constituted a real risk to competition".

The Court ordered Alinta to pay the ACCC's court costs.