What happened? Bloomberg reported that RIO (+) and Glencore (+) have discussed a potential combination of the two businesses in what could be the industry''s largest ever deal. Neither company has commented and it is unclear whether discussions even remain live. We expect these headlines to raise eyebrows and we struggle to see the logic behind the conceptual transaction given the lack of product and geography overlap and divergent corporate cultures. We believe it''s a low probability a deal in this format would go ahead and be supported by shareholders. BNPP Exane View: Scale for scale''s sake? A conceptual combination of RIO and Glencore would create a mining behemoth and leap-frog BHP in market capitalisation. But would this really matter and this couldn''t be a major motivator, in our opinion, as neither gets passed over by investors for not being large or liquid enough. Combining the two copper businesses (figure 1) would create the world''s largest copper producer but also draw strict anti-competition review in our opinion. Not an ideal fit Beyond copper, we don''t see where the rationale lies to combine the businesses and even in the red metal Glencore has assets in Africa''s where RIO has historically shied away from. Perhaps the biggest contrast on commodity views is coal which RIO completely exited in 2018 (and even sold some assets to Glencore) whereas Glencore completed the acquisition of EVR and announced its intention to keep coal in the portfolio just c6 months ago. The motivation for RIO is harder to understand On multiple levels we see the strategic rationale difficult to understand but first and foremost bringing coal back into the portfolio would be a strategic U-turn and could weigh on RIO''s valuation multiple and cause some UK/Euro funds to be forced sellers. While RIO would be adding more copper to the portfolio, it would be bringing an ex-growth portfolio at a time when its own asset portfolio is growing (figure 2). We can see the...