Benjamin Graham specifies three different Intrinsic Value calculations — the Graham Number, the Enterprising price calculation and the NCAV — in his framework, with supporting qualitative rules for each.
Graham also wrote extensively about the unreliability of estimates in finance. His actual framework only uses objective past and present figures, and requires no subjective assumptions about the future.
So, a stock's intrinsic value is not subjective; at least, not according to Value Investing as taught by its founder.