The case is set to throw into the spotlight, the question as to whether forced retirement should be justifiable to make way for young talent coming through.
With the removal of the default retirement age, and the fact age discrimination claims overtook race discrimination claims in 2011 in terms of numbers, whatever is decided in Seldon will have much broader application.
Commenting in advance of the hearing, Paul McFarlane, partner in the employment team at law firm Weightmans, said: "It will be interesting to see what view(s) the Supreme Court takes on whether the legitimate aims are justifiable. What makes this Supreme Court decision potentially more significant than when it was first heard; is that the default retirement age provisions, previously contained in the Regulations, have now been repealed. Accordingly, all employers, who continue to use a retirement age, will now have to show what the legitimate aim(s) is/are for its continued use; and show that their legitimate aim(s) are proportionate i.e. both necessary and appropriate.
"With the removal of the default retirement age, it must be questioned whether having a congenial and supportive culture in a firm, which does not need to have performance management, is both necessary and appropriate?
"Similarly, will it now be enough to put forward as a legitimate aim of enabling associates to move up the ranks? Even if this is considered to be a legitimate aim, will its continued use be considered proportionate?
"A retirement age could be said to assist in the fight against youth unemployment as when vacancies are created towards the top end of an organisation, this will have a drip down effect and create new posts at the junior end of an organisation. Yet this argument only works if you work on the assumption that junior roles are filled by junior (read younger) members of staff and vice-versa - which would appear to go against the very thing that age discrimination law has been brought in to prevent i.e. employers making assumptions on an employees' capabilities based on their age.
"It will be interesting to see whether the Supreme Court considers these issues and, if so, what its views are on them."
Lou Marshall, solicitor at Fladgate the law firm, added: "The Seldon case, which opens in the Supreme Court this week is now more relevant than ever given that the default retirement age has been abolished and so more people may be affected by the outcome especially in an economic climate where are looking to work for as long as possible. My hope is that the outcome of this case will move us away from the assumption that there is necessarily a link between an individual's age and their ability to carry out their role. And simultaneously, move us a step closer to a more inclusive and merit-based approach to employment (where outmoded assumptions are abandoned)."