Key takeaways:

• Broker upgrades and takeover activity occupy the headlines this week

As the Federal Reserve pushed ahead with its rate hike program this week, attention shifted to a number of local developments including M&A activity.

Which shares excelled?

Nickel producer Mincor Resources (ASX: MCR) is flying higher after the company found itself the centre of a takeover approach from none other than Andrew Forrest. The mining magnate Wyloo Metals lobbed an offer at Mincor, valuing the company at $760 million. 

Wyloo is already the largest shareholder on the register, with a stake of 19.9%, albeit Mincor has advised the rest of its shareholders not to take any further action with regards to the $1.40 per share offer at this time.

Yet again, gold stocks are leading the winners list across the ASX this week. Despite further interest rate hikes in the US and the UK, the price of the precious metal is flirting with US$2,000 per tonne as the fallout of the banking blow-up continues to reverberate across financial markets. 

Some of the outperformers include Evolution Mining (ASX: EVN), Resolute Mining (ASX: RSG), Perseus Mining (ASX: PRU), Bellevue Gold (ASX: BGL), and Newcrest Mining (ASX: NCM).AGL Energy (ASX: AGL) is the beneficiary of a positive broker upgrade, with investors warming to Macquarie coverage of the energy business. The broker argues that AGL shares are currently undervalued on account of the retailer exposure to higher electricity prices. On the back of this tailwind, Macquarie has slapped an outperform' rating on the stock, alongside a target price of $8.31 per share.Another name taking in the upside of broker coverage is Domino Pizza (ASX: DMP). The fast food franchise was upgraded to an overweight' rating by Barrenjoey, with one of the retailer toughest headwinds starting to fade. With inflation starting to unwind, and the economic reopening now in full swing, the broker argues the root causes behind Domino struggles are looking like they could be a thing of the past. At the same time, Barrenjoey also believes Domino is well placed to capture market share and restore margins.Elsewhere, pathology and diagnostics business Healius (ASX: HLS) is in the spotlight as it also received a takeover proposal. In rather unique circumstances, that approach has come from a smaller rival, with Australian Clinical Labs (ASX: ACL) offering Healius shareholders 0.74 shares in ACL for every HLS share they hold. Although the bid did not include a premium, ACL is touting the potential synergies and valuation upside of the all-scrip off-market takeover bid.New Hope (ASX: NHC), United Malt Group (ASX: UMG), Iress (ASX: IRE), and Domain Holdings Australia (ASX: DHG) are just some of the other names on watch after a standout week.

Which shares dragged on the market?

Afterpay owner Block (ASX: SQ2) is in the firing line today after the tech firm was the subject of a short report. In a detailed research report, Hindenburg accused the payments company of facilitating fraudsters. As part of a two-year investigation, Hindenburg alleges that Block Cash App likely facilitated scammers in taking advantage of government-funded stimulus programs throughout the pandemic. 

That stems from US data out of Massachusetts suggesting individuals were using the same bank account numbers to receive government funds. Furthermore, Block is being accused of overstating user numbers for Cash App, while the company interchange fees and acquisition of Afterpay were also cited as problems. In responding to the report, Block indicated it will explore legal action against Hindenburg, suggesting the report is designed to deceive and confuse investors.

Shares in semiconductor memory tech firm Weebit Nano (ASX: WBT) were pummelled this week after the company exited a trading halt arising from an institutional placement. The company raised $45 million based on 9 million shares priced at $5 a piece, but the share price quickly tumbled below that level when trading resumed. A further $10 million is being sought via a Share Purchase Plan, with proceeds earmarked to help the company develop and commercially progress its ReRam technology.Battery metals remain out of favour at this time, with the segment unable to build on the momentum of recent years. Pricing concerns appear to be one of the headwinds for the sector, and this week UBS indicated that it sees lithium supply potentially doubling over the next couple years as the likes of China and Latin America boost their output. Sayona Mining (ASX: SYA), Liontown Resources (ASX: LTR), and Arafura Rare Earths (ASX: ARU) are some of the laggards.Ex-dividend status weighed on Myer (ASX: MYR) share price, with the retailer recently opting to reward its shareholders with an interim and special dividend. When the company reported its half-year results at the start of March, management declared a fully-franked interim dividend of 4 cents per share, as well as a special dividend of equal size. Shareholders will receive the payment for said dividends on May 11.After company Chairman David Williams sold a large number of shares this week, Polynovo (ASX: PNV) is also lagging the rest of the market. Mr Williams sold a total of 4.75 million shares between March 17 and March 22, representing approximately $9.7 million worth of holdings. 

Although the company indicated that the sale was prompted by Mr Williams needing the money to settle a property purchase in the US, and that he still holds over 21 million shares, other shareholders responded to the sale by following suit.

Investors have also been quick to ditch the likes of Champion Iron (ASX: CIA), Paladin Energy (ASX: PDN), GQG Partners (ASX: GQG), and Coronado Global (ASX: CRN).

We'll be back next week with another Weekly ASX Trading Wrap Up - until then, have a great week!