HAMILTON, Ont. – Hundreds of members of the United Steelworkers are off the job in Hamilton after being locked out by U.S. Steel, which is demanding a vote on a "final" contract offer that demands a basket of employee concessions.

Workers at the former Stelco plant set up picket lines after the company locked them out Sunday night in the ongoing contract dispute.

In New York, stock in U.S. Steel (NYSE:X) shares was down 75 cents, or 1.55 per cent, at US$47.75 in midday trading.

The Pittsburgh company is demanding that its latest offer, made Nov. 4 and delivered through a mediator appointed by the provincial Ministry of Labour, be put to the workers for a vote.

The company says the changes are needed for the plant to be competitive.

With the Canadian dollar near parity with its U.S. counterpart, multinational companies like U.S. Steel that have operations on both sides of the border – as well as in Mexico – are under pressure to make sure costs are comparable where they operate since the steel market is global.

That means the cost of producing steel in Hamilton or Nanticoke, on the shores of Lake Erie, is compared with major plants near Pittsburgh – in Clairton and Braddock Pa. – that U.S. Steel still operates.

The American company, with 43,000 workers, has about 25 plants in North America, Europe and Brazil.

At the former Stelco, the main sticking points have been the company’s demand for concessions on pensions, the cost of living formula and benefits.

Among other things, the company wants the existing defined benefit pension plan closed to new employees and replaced with a defined contribution retirement savings plan. It also wants an end to the indexing of pension payments for current retirees.

The head of Steelworkers Local 1005, Rolf Gerstenberger, has refused to take the offer to the membership because he said it would amount to having the current 900 members change the contact for past employees – the retirees.

"Let me ask you this about a vote. It’s supposed to be democratic. How can 900 people vote that 9,000 people should get shafted. How does that work, how is that democracy?" he told supporters.

U.S. Steel is also in a court battle with Ottawa over promises it made under when it acquired Stelco for more than $1 billion in 2007.

Ottawa says the company broke its production and employment undertakings when it idled most of its Canadian operations – which include the Hamilton plant and another facility in Nanticoke, Ont., – in early 2009.

Workers in Nanticoke resolved an eight-month lockout in April.

The current lockout comes as the steel industry’s goes through hard times.

U.S. Steel had a net loss of US$51 million in the third quarter and the last time it posted a quarterly profit was at the end of 2008.