Although it doesn't happen very often, there are occasions when the manager decides to change the basis on which a particular fund or investment trust operates.
This may involve, for example, switching to a new benchmark index, as Henderson Global Trust did in 2013 - reflecting the fund's greater focus on the US and less on the UK.
Or it could mean taking a different focus in the investment strategy - for example concentrating more on equities rather than a mix of assets, as Alliance Trust's board decided to do in 2015).
Other mandate changes could include adjusting the target income for the fund or trust, changing its geographical focus (as Old Mutual did with its China Equity fund in 2015, giving it more flexibility to invest in stocks related to mainland China), or outsourcing portions of the portfolio to third party managers (as Witan investment trust started to do in 2004).
Any alteration in a fund's remit should be pause for thought for an investor, but it is not necessarily a signal to cut and run.
'When most mandates are changed I would call it generally a tinkering around the edges to expand the investment opportunities available to the fund,' says Andy Parsons, head of investment research and advisory services at The Share Centre.
In deciding what to do in the event of a change Parsons says investors should ask themselves why they were initially attracted to that fund.
'If it focuses on a specific geographic region, for example, and that is being expanded, ask yourself if you are comfortable with how far the fund can now go and if it still fits with your beliefs and your risk appetite,' he adds.
Also consider how big a change is it and whether it will fundamentally change the fund's remit.
'It is important to understand how the change will affect the manager's strategy in the future,' says Ian Williams, managing director at Cavendish Online. He thinks instances where a fund moves from, say, a growth to an income focus will have a bigger impact.
'I would take stock and see what happens over the next six to nine months,' says Parsons. 'Not all of the changes will be made in the first month: they can take up to a year, so maybe don't put more money in but watch the fund and consider some alternatives,' he adds.
However, Parsons says the situation may require swifter action if the change results in the fund moving Investment Association (IA) or Association of Investment Companies (AIC) sectors, as that can have an additional effect on its remit.
'Sometimes changes occur because a fund has been very successful and experienced big inflows, so the mandate needs to move to make it easier for the manager to manage the fund, and to make it more flexible,' points out Parsons.
While this may be an indication of the fund's success, a shift from mid to large cap may mean it no longer fits with investors' needs.
'Investors should check the fund will continue to fulfil its role in their portfolio, that it still fits their risk strategy and doesn't create too much of an overlap in their fund selection,' agrees Williams.
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