Industrial investment conglomerate Melrose saw its long-running Chairman invest over six and a half millions pounds in the company this week.Harris & Sheldon Investments, an investment company connected with Executive Chairman Christopher Miller, purchased 2.76m shares through three transactions between June 24th and June 26th, spending a total of £6.64m.Miller, who joined the board back in 2003, now has a holding in Melrose of nearly 17m shares (equal to 1.34% of the issued share capital), 6.8m of which is held by Harris & Sheldon.The transactions came just a few days after Melrose confirmed the sale of motor manufacturing division Marelli Motori for €212m (£181m), a higher price than analysts were estimating.In a research report last week, broker Investec pointed out that the sale - combined with other disposals this year - increased the likelihood that Melrose could announce a "sizeable" cash return of around 50p a share, possibly by the end of 2013.Top Director BuysMelrose Industries (MRO) Director name: Mr James Christopher MillerAmount purchased: 1,651,480 @ 243.31p Value: £4,018,216Melrose Industries (MRO) Director name: Mr James Christopher MillerAmount purchased: 1,066,975 @ 236.69p Value: £2,525,530Liontrust Asset Management (LIO) Director name: Mr John Stephen IonsAmount purchased: 59,146 @ 192.50p Value: £113,856Melrose Industries (MRO) Director name: Mr James Christopher MillerAmount purchased: 41,545 @ 243.71p Value: £101,249Liontrust Asset Management (LIO) Director name: Mr Vinay Kumar AbrolAmount purchased: 39,602 @ 192.50p Value: £76,234Ariana Resources (AAU) Director name: Mr Michael de VilliersAmount purchased: 3,636,360 @ 1.00p Value: £36,364F&C Asset Management (FCAM) Director name: Mr Edward BramsonAmount purchased: 36,000 @ 94.73p Value: £34,103British Assets Trust (BSET) Director name: Mr James MacleodAmount purchased: 25,000 @ 125.75p Value: £31,438Imagination Technologies Group (IMG) Director name: Mr David Hurst-BrownAmount purchased: 10,000 @ 292.40p Value: £29,240SimiGon Ltd. (DI) (SIM) Director name: Mr Alistair RaeAmount purchased: 36,250 @ 28.00p Value: £10,150