A stroppy session of one of Westminster's most powerful committees and one of the world's biggest businesses is just drawing to close.
Google UK boss Matt Brittin is facing questions from MPs over where it makes its ad money - and whether they should be paying more tax here.
YouTube is introducing a monthly paid subscription service, including shows like Sesame Street.
– Richard Murphy, director of Tax Research UK
Google are asking us to believe that they don't sell to their UK customers - and even those customers don't believe that.
Google are playing a game with the international tax system - and that's how they created their monopoly.
Amyas Morse, the head of the National Audit Office, has told Google UK boss Matt Brittin that the issue over the tech giant's tax bill was not "going away" because people remained sceptical.
"There are a tonne of people who are listening and saying we think they are selling in the UK," he told the Google boss.
Google UK's boss has said the company grows the business by encouraging people to spend money.
In a testy exchange, Margaret Hodge, Chair of Commons' Public Accounts Committee said they "grow the business by selling".
Brittin said "we could debate sales and what constitutes sales all day..but that isn't the issue''
"Yes it is", said Hodge.
Margaret Hodge has said the committee had been contacted by a "stream of whistleblowers" who had provided evidence suggesting that sales activity was taking place in the UK.
Hodge said she had seen an invoice sent to clients by Google from a London address, as well as a presentation describing steps of the selling process involving UK-based staff.
The committee had also been contacted by a senior salesman who she said was paid a "modest" salary, but three or four times that in commission for sales he made and for "closing deals", Mrs Hodge said.
Mr Brittin said that, although sales staff in the UK were promoting Google and encouraging people to spend money, the transaction would take place with Ireland.
"What people are not doing, any customer that spends with us, they have to buy from Ireland because that's where the intellectual property sits."
Google UK boss Matt Brittin has said Dublin was Google's largest operation in Europe with 3,000 staff and that any advertiser in Europe contracts with Google in Ireland.
He said: "When we came to Europe we set up Dublin as our European headquarters pretty rapidly.
"We set that up because we wanted to be able to contract with customers across the whole of Europe, not just the UK."
Internet giant Google has denied trying to "disguise" the way its business operated to minimise its tax bill in the UK.
Google UK boss Matt Brittin insisted he stood by evidence he gave last year that all the firm's advertising in Europe was sold through its offices in Ireland.
Committee chairman Margaret Hodge said his claims were contradicted by documentation MPs had seen and evidence from a "stream" of whistleblowers.
Mr Brittin said the evidence related to the period before he joined the company six and half years ago and that suggestions that Google was trying to "disguise" the way it operated were "just not true".
"I stand by what I said. I described very clearly how we operate," he said.
Google UK boss Matt Brittin's key quote from previous evidence is "anyone who buys advertising from us in Europe buys from Google in Ireland".
That is only one phrase from a pretty lengthy evidence session but it is what the Commons' Public Accounts Committee is focusing on.
It is true Google's deals are booked and accounted for in Ireland - what the committee are trying to establish is where the deals are actually done.
Google UK boss Matt Brittin is being questioned by the Commons' Public Accounts Committee over the tech giant's tax bill.
Today's Google grilling comes as the chairwoman of the committee, Margaret Hodge, revealed that Amazon also faced being hauled back to explain its financial dealings.
- Amazon may employ thousands of people in the UK, but its European headquarters is in the tax haven of Luxembourg, where it employs several hundred staff.
- Consumers buy from the company's UK website and the items are delivered from British warehouses.
- But they and people buying from Amazon websites in other European countries are buying items from a company called Amazon EU Sarl, in Luxembourg.
- This allows the company to legitimately lower its tax bill. It is taxed at the lower rate in Luxembourg.
- Amazon's main UK subsidiary paid just £3.2m in tax last year, according to accounts filed on Wednesday, despite overall UK sales of £4.2bn.
Read more: Amazon paid £3m tax on £4bn UK sales