Fairfax stock positions

[Viking]

If I was Fairfax, what would be my next take-private equity purchase? Probably Dexterra. Yes, not a needle mover. But it would be a solid addition to their current collection of private companies.

 

Why? Dexterra is dirt cheap (the stock), generates solid free cash flow and has solid growth prospects. And Fairfax has the cash.

 

What is the Dexterra story?

 

in 2018, Fairfax purchased Carillion Canada out of bankruptcy. The problem with Carillion was its UK parent went bankrupt. Fairfax paid about 5 times free cash flow for the Canadian operations. In 2020, Dexterra acquired Horizon North Logistics in a reverse takeover. Fairfax owned 49% of the combined company. This deal closed in May of 2020 (as covid was raging). At the time, Dexterra’s CEO, John MacCuish, set the audacious target for C$1 billion in revenue and C$100 million in EBITDA in the ‘next few years’.

 

How is the company doing? After hitting a speed bump in 2022, Dexterra is on track to achieve both of their financial targets in 2024. As part of an updated 5-year vision just unveiled today at the AGM, a new C$2 billion revenue target has been set. The growth at Dexterra is being funded by internally generated cash and debt (which is reasonable). EBITDA conversion to free cash flow is expected to be 50%.

 

What was the speed bump in 2022? Inflation knocked two business units on their ass:

1.) IMF: was not able to reprice contracts quick enough

2.) Modular Solutions: BC contracts did not have inflation clause (CEO of this division has since left)

 

In Q1, 2023 we learned IMF profitability is getting back to targeted levels. In modular, the remainder of the unprofitable BC contracts will be run off in Q2 and Q3 (the financial hit was largely already booked in Q4, 2022). The turnaround in modular will likely be a late 2023 or 2024 story.

 

Bottom line, 2023 is shaping up to be a decent year for the company. More acquisitions are coming. Growth should pick up again in 2024. Dividend yield is a solid 6.8% (with no risk of being cut). Chug, chug, chug.

 

- https://dexterra.com/wp-content/uploads/2023/05/2023-AGM-Presentaion.pdf

- https://dexterra.com/wp-content/uploads/2023/05/Analyst-Presentation-v6-Q1-2023.pdf

—————

Dexterra (DXT.TO)

• Stock price = C$5.15
• Market cap = C$335 million
• Dividend = C$0.0875/share = $0.35/year = 6.8% yield
• 2023 revenue est = C$1 billion
• 2023 EBITDA est = C$85 million
• 2023 free cash flow est = C$40 million

—————

What are Dexterra’s businesses? It is a really diverse collection of businesses.

1.) Integrated Facilities Management (IFM)

 - growth engine

2.) Workforce Accommodations, Forestry, Energy Services (WAFES)

3.) Modular Solutions

 

- https://dexterra.com/wp-content/uploads/2021/03/Dexterra_ServicingTheFuture_Brochure.pdf

—————

—————

What would it cost Fairfax to buy the 51% of Dexterra they do not own? 

• C$6.50/share? x 33.2 million shares = $222 million?

If Dexterra shares continue to trade in the low C$5 range in 2023 I think Fairfax may swoop in and take the company private similar to what they did with Recipe in 2022. Like with Recipe, have Dexterra fund part of the cost with debt (which they can then quickly pay off). Opportunistic. Smart.  

—————

2022AR: Dexterra is on track to achieve its vision of becoming a leader in delivering quality solutions to create, manage and operate infrastructure. John MacCuish is retiring after an outstanding performance for us, from rescuing Carillion from bankruptcy to the merger with Horizon North to form Dexterra. A big thank you to John for his leadership and dedication to Dexterra and best wishes to him and his family for a long and healthy retirement. The new CEO Mark Becker has been a senior leader in the organization for several years and is supported by three strong business unit Presidents. Dexterra closed two important integrated facilities management acquisitions early in the year and, coupled with organic growth, this strategic business unit almost doubled in size in 2022. The workforce accommodations segment also continued to build market share and deliver strong profitability while capitalizing on higher activity levels in Canada’s resource industries, although Dexterra’s modular business experienced short-term profitability challenges given high inflation and supply chain disruptions. Management expects to continue to build its modular platform and diversify its product mix, with strong demand for social and affordable housing across Canada.

—————

2021AR: Dexterra remains on track to achieve Cdn$1.0 billion in sales and Cdn$100 million in EBITDA in the near term. John MacCuish is leading the transformation to be a capital-light business. The workforce accommodations segment experienced strong growth and had strong profitability as resource industries in Canada rebounded in 2021. The strong underlying demand in affordable housing across Canada is also a priority for both the federal and provincial governments, and Dexterra’s modular solution business is in an excellent position to support this very important social issue. In January 2022, Dexterra also closed two facilities management acquisitions at attractive multiples with a combined purchase price of approximately Cdn$50 million. Dana Hospitality expands the company’s existing culinary services into education, entertainment, healthcare and leisure activities. Tricom Facility Services group, a business with a long history of providing janitorial and building maintenance services, builds the company’s strength in the hospitality, transit and entertainment verticals. These acquisitions have been financed by the company’s existing credit facility and the company’s balance sheet continues to be strong to support future growth.

—————

2020AR: The development of Dexterra’s business was dramatically reshaped by the reverse takeover in May 2020 of Horizon North. Dexterra, now a listed public company and led by John MacCuish, has a vision to build a Canadian support services champion. Its activities include a comprehensive range of facilities management, workforce accommodations, and forestry and modular build capabilities, including being a leader in social housing projects. Dexterra has publicly stated that it is on course in the next few years for Cdn$1 billion in revenue and Cdn$100 million in EBITDA.

 

Acquisition of Horizon North Logistics

On May 29, 2020 Horizon North Logistics Inc. (‘‘Horizon North’’) legally acquired 100% of Dexterra by issuing common shares to the company representing a 49.0% equity interest in Horizon North. The company obtained de facto voting control of Horizon North as its largest equity and voting shareholder and accounted for the transaction as a reverse acquisition of Horizon North by Dexterra. The assets, liabilities and results of operations of Horizon North were consolidated in the Non-insurance companies reporting segment. Horizon North, which was subsequently renamed Dexterra Group Inc. (‘‘Dexterra Group’’), is a Canadian publicly listed corporation that provides a range of industrial services and modular construction solutions.

—————

2019AR: Dexterra continues to provide industry-leading facilities management and operation solutions in Canada under the leadership of John MacCuish, its CEO. Bill McFarland is also Chair of Dexterra. The company continues to be the go-to service provider for some of the country’s largest airports, premier retail and commercial properties, corporate campuses, research and education facilities, large industrial sites, defence and public assets, camps and catering and state-of-the-art healthcare infrastructure. The company is also one of the country’s largest reforestation contractors and forest firefighters.

—————

2018AR: I am happy to report that we also made two significant private company investments in 2018/2019 – Dexterra and AGT. Dexterra, led by John MacCuish as CEO, is the new name for Carillion Canada which went into bankruptcy because of the bankruptcy of its parent in the U.K. Dexterra provides industry-leading facilities management and operation solutions across Canada, including maintenance solutions for over 50 million sq. ft. of high-quality infrastructure. This includes some of the country’s largest airports, premier retail and commercial properties, corporate campuses, research and education facilities, large industrial sites, defence and public assets and state-of-the-art healthcare infrastructure. The company is also one of the country’s largest reforestation contractors – planting over 40 million trees annually, it annually completes 4,400 hectares of forest thinning/brushing and 1,200 hectares of site preparation–it employs hundreds of firefighters, with an emphasis on Indigenous communities, and for the last 30 years it has been supplying and operating full-service remote workforce services. We were able to buy Dexterra at about 5x free cash flow.

 

Acquisition of certain businesses of Carillion Canada Inc.

On March 7, 2018 the company acquired the services business carried on in Canada by Carillion Canada Inc. and certain affiliates thereof relating to facilities management of airports, commercial and retail properties, defense facilities, select healthcare facilities and on behalf of oil, gas and mining clients. The acquired business was subsequently renamed Dexterra Integrated Facilities Management (‘‘Dexterra’’). Dexterra is an infrastructure services company that provides asset management and operations solutions to industries and governments. The assets and liabilities and results of operations of Dexterra were consolidated in the Other reporting segment.

 

Purchases of subsidiaries, net of cash acquired of $163.1 in 2018 primarily related to the acquisitions of Dexterra (100%) and Toys ‘‘R’’ Us Canada (100%).

Edited May 11, 2023 by Viking

[petec]

On 5/11/2023 at 6:27 AM, Viking said:

If I was Fairfax, what would be my next take-private equity purchase? Probably Dexterra.

 

Stelco is the other one that makes sense to me, but might be harder to get AK over the line.

 

Am I right that the Brit stub buyout option expires later this year? That might be the next one to go.

[Luca]

Micron now the biggest holding for Fairfax for the US in latest 13 F. Atlas was sold 100%, 220% increase for Occidental. Interesting!

[gfp]

41 minutes ago, Luca said:

Micron now the biggest holding for Fairfax for the US in latest 13 F. Atlas was sold 100%, 220% increase for Occidental. Interesting!

 

Well I'm not sure it is accurate to say "Atlas was sold 100%."

 

(if anything it was an "add" since they exercised warrants for $78.7 million in cash during the quarter)

Edited May 15, 2023 by gfp

[Daphne]

Didn’t atlas go private?

[Luca]

Ah never mind, i think you are right

[newtovalue]

Fairfax now has a larger position in ORLA ($70MM position) - junior gold producer in Nevada, Mexico and Panama.

 

I've never heard of the company - wondering if anyone on the board has?

[dartmonkey]

On 5/15/2023 at 7:54 AM, Luca said:

Micron now the biggest holding for Fairfax for the US in latest 13 F. Atlas was sold 100%, 220% increase for Occidental. Interesting!

It's interesting to see how many Berkshire picks end up in Watsa's portfolio. There was already some Occidental and Chevron, and now more Occidental, just like in Berkshire, and no additional Chevron, while Berkshire is selling Chevron. In banks, both companies used to own Wells Fargo, and now, both have big positions in Bank of America (although Fairfax also owns a bit of Citigroup and Bank of Nova Scotia). Just one car builder in both portfolios, and it's GM. Both had Taiwan Semiconductor, although Berkshire has sold its stake recently. Activision arbitrage - yes, in both cases, but both have been reduced this quarter.

 

Great minds think alike? But it seems like a bit too much overlap for it to be coincidence. 

[Luca]

9 minutes ago, dartmonkey said:

It's interesting to see how many Berkshire picks end up in Watsa's portfolio. There was already some Occidental and Chevron, and now more Occidental, just like in Berkshire, and no additional Chevron, while Berkshire is selling Chevron. In banks, both companies used to own Wells Fargo, and now, both have big positions in Bank of America (although Fairfax also owns a bit of Citigroup and Bank of Nova Scotia). Just one car builder in both portfolios, and it's GM. Both had Taiwan Semiconductor, although Berkshire has sold its stake recently. Activision arbitrage - yes, in both cases, but both have been reduced this quarter.

 

Great minds think alike? But it seems like a bit too much overlap for it to be coincidence. 

I think Fairfax is looking at 13Fs and at what others do and applies all the tools they have to create returns, probably cloning some positions, throwing in some own ideas, quite interesting.

[Saluki]

I hadn't heard of Orla before, and I hate junior miners, but it's a big position, and I remember a few years back Prem bought a rights offering for a $100mm potash company and that went from $1 -$4 in a year, so it's worth digging into the annual report to see if you can figure out what he sees in it. Even if you pass on it, and just participate indirectly through FFH, it's a good learning exercise. 

 

Since ATCO is private now, I assume there will be some discussion of how it's valued going forward when the new ships are delivered and whether that nice fat dividend will still keep coming to FFH like it was to shareholders. 

[Crip1]

2 hours ago, dartmonkey said:

It's interesting to see how many Berkshire picks end up in Watsa's portfolio. There was already some Occidental and Chevron, and now more Occidental, just like in Berkshire, and no additional Chevron, while Berkshire is selling Chevron. In banks, both companies used to own Wells Fargo, and now, both have big positions in Bank of America (although Fairfax also owns a bit of Citigroup and Bank of Nova Scotia). Just one car builder in both portfolios, and it's GM. Both had Taiwan Semiconductor, although Berkshire has sold its stake recently. Activision arbitrage - yes, in both cases, but both have been reduced this quarter.

 

Great minds think alike? But it seems like a bit too much overlap for it to be coincidence. 

Investing returns is a simple numbers game, there are no style points for leveraging the knowledge/acumen of others. 

 

-Crip

[dartmonkey]

4 hours ago, Crip1 said:

Investing returns is a simple numbers game, there are no style points for leveraging the knowledge/acumen of others. 

 

-Crip

No, I know, I didn't mean to sound critical - I think most of us would be happy if Fairfax's equity investments more closely resembled Berkshire's!

[Parsad]

9 hours ago, dartmonkey said:

It's interesting to see how many Berkshire picks end up in Watsa's portfolio. There was already some Occidental and Chevron, and now more Occidental, just like in Berkshire, and no additional Chevron, while Berkshire is selling Chevron. In banks, both companies used to own Wells Fargo, and now, both have big positions in Bank of America (although Fairfax also owns a bit of Citigroup and Bank of Nova Scotia). Just one car builder in both portfolios, and it's GM. Both had Taiwan Semiconductor, although Berkshire has sold its stake recently. Activision arbitrage - yes, in both cases, but both have been reduced this quarter.

 

Great minds think alike? But it seems like a bit too much overlap for it to be coincidence. 

 

You will probably see more similarities over time to Berkshire and Markel.  Wade and Lawrence invest more like Buffett and Gayner.  Whereas the old Hamblin-Watsa gang were more deep distressed equity/bond investors like Ben Graham or Seth Klarman.

 

As the younger guys have more influence, and the older guys less influence, you'll see the portfolio behave more like Berkshire or Markel.

 

Cheers!  

[nwoodman]

7 hours ago, Parsad said:

 

You will probably see more similarities over time to Berkshire and Markel.  Wade and Lawrence invest more like Buffett and Gayner.  Whereas the old Hamblin-Watsa gang were more deep distressed equity/bond investors like Ben Graham or Seth Klarman.

 

As the younger guys have more influence, and the older guys less influence, you'll see the portfolio behave more like Berkshire or Markel.

 

Cheers!  

I for one won’t mind in the least .  Thanks for providing a little more colour.

[petec]

On 5/16/2023 at 8:55 PM, dartmonkey said:

No, I know, I didn't mean to sound critical - I think most of us would be happy if Fairfax's equity investments more closely resembled Berkshire's!

 

Not me. I can own Berkshire and Markel myself. I far prefer Fairfax to do something different and hope they continue. 

[glider3834]

Grivalia Hospitality 

 

Grivalia appears to have had operating loss in Q1'23 but it looks like they are still in build out phase - they are aiming for completion on three projects

According to Chryssikos, the third (three?) projects under construction will open as pilot operations very soon; Avantmar in June; the Glyfada project in early August; and the Voula Project in early 2024.

 

but have additional ones planned, so I assume once they ramp up there would be revenue contribution there.

 

https://www.ekathimerini.com/economy/1210801/aiming-for-wealthy-guests/

 

'For the Grivalia CEO, there is a great market for 5- and 6-star resorts in Greece. Demand is high and, so far, supply is low. And the targeted cliented is high value: people with considerable disposable income who are going to spend large sums that will benefit the whole tourism ecosystem.'

 

 

Edited May 18, 2023 by glider3834

[gfp]

KW / PACW transaction.  Fairfax likely benefits

https://www.cnbc.com/2023/05/22/pacwest-bancorp-to-sell-real-estate-loans-to-kennedy-wilson-subsidiary.html

 

https://www.sec.gov/ix?doc=/Archives/edgar/data/0001102112/000110465923062856/tm2316420d1_8k.htm

Edited May 22, 2023 by gfp

[dartmonkey]

On 5/22/2023 at 7:12 AM, gfp said:

KW / PACW transaction.  Fairfax likely benefits

https://www.cnbc.com/2023/05/22/pacwest-bancorp-to-sell-real-estate-loans-to-kennedy-wilson-subsidiary.html

 

https://www.sec.gov/ix?doc=/Archives/edgar/data/0001102112/000110465923062856/tm2316420d1_8k.htm

Yes, Fairfax owns only 10% of KW but they have billions invested via KW, so KW increasing their footprint by about 10% could be very good for Fairfax, particularly if Fairfax has invested alongside KW to provide liquidity for PacWest. On the other hand, no press release from Fairfax probably means that Fairfax does not have significant financing in this deal, so while this is probably a great deal for KW, it may have limited impact on Fairfax.

[Viking]

How are Fairfax's equity holdings (that I track) doing at about the 60% mark for the quarter? They are up about $500 million = $22/share pre-tax. 

• mark to market = +$130 million
• associate =          +$370 million
• consolidated =           flat

Big movers?

1. Eurobank = +$430 million
2. FFH TRS =  +$105 million
3. Stelco =        ($88 million)

Bottom line, after a very strong Q1, the equity holdings are trending very well in Q2. Eurobank today has a market cap of $1.97 billion. Atlas is at $2.04 billion. As @glider3834 predicted not that long ago, Eurobank could shortly become Fairfax's largest equity investment. 

----------

I updated my spreadsheet to capture the changes from the Q1 13F. I also re-ordered the ranking of the holdings by size. 

Fairfax Equity Holdings May 23 2023.xlsx

[nwoodman]

30 minutes ago, Viking said:

How are Fairfax's equity holdings (that I track) doing at about the 60% mark for the quarter? They are up about $500 million = $22/share pre-tax. 

• mark to market = +$130 million
• associate =          +$370 million
• consolidated =           flat

Big movers?

1. Eurobank = +$430 million
2. FFH TRS =  +$105 million
3. Stelco =        ($88 million)

Bottom line, after a very strong Q1, the equity holdings are trending very well in Q2. Eurobank today has a market cap of $1.97 billion. Atlas is at $2.04 billion. As @glider3834 predicted not that long ago, Eurobank could shortly become Fairfax's largest equity investment. 

----------

I updated my spreadsheet to capture the changes from the Q1 13F. I also re-ordered the ranking of the holdings by size. 

Fairfax Equity Holdings May 23 2023.xlsx 279.61 kB · 5 downloads

Thanks Viking

[Viking]

On 5/17/2023 at 11:16 PM, glider3834 said:

Grivalia Hospitality 

 

Grivalia appears to have had operating loss in Q1'23 but it looks like they are still in build out phase - they are aiming for completion on three projects

According to Chryssikos, the third (three?) projects under construction will open as pilot operations very soon; Avantmar in June; the Glyfada project in early August; and the Voula Project in early 2024.

 

but have additional ones planned, so I assume once they ramp up there would be revenue contribution there.

 

https://www.ekathimerini.com/economy/1210801/aiming-for-wealthy-guests/

 

'For the Grivalia CEO, there is a great market for 5- and 6-star resorts in Greece. Demand is high and, so far, supply is low. And the targeted cliented is high value: people with considerable disposable income who are going to spend large sums that will benefit the whole tourism ecosystem.'

@glider3834 this part got my attention: “When the five planned projects are completed, Grivalia’s value, currently nearly €1 billion, will reach €1.5 billion, says Chryssikos.”

 

I am not sure what exactly Chryssikos is referencing. Fairfax owns 78% of Grivalia Hospitality with a carrying value/market value = $410 million (Dec 31, 2022).
 

The cost to develop and run these properties must be staggeringly high. Grivalia Hospitality will likely bleed significant sums of money until more locations are open and generating significant revenue. Interesting investment. Chryssikos has had the Midas touch for Fairfax when it comes to real estate in Greece. And we know Fairfax loves to bet heavily on winning horses…

 

 

Edited May 24, 2023 by Viking

[glider3834]

18 hours ago, Viking said:

@glider3834 this part got my attention: “When the five planned projects are completed, Grivalia’s value, currently nearly €1 billion, will reach €1.5 billion, says Chryssikos.”

 

I am not sure what exactly Chryssikos is referencing. Fairfax owns 78% of Grivalia Hospitality with a carrying value/market value = $410 million (Dec 31, 2022).
 

The cost to develop and run these properties must be staggeringly high. Grivalia Hospitality will likely bleed significant sums of money until more locations are open and generating significant revenue. Interesting investment. Chryssikos has had the Midas touch for Fairfax when it comes to real estate in Greece. And we know Fairfax loves to bet heavily on winning horses…

 

 

@Viking so this video below has terrible sound quality but from 27-32 min mark - George outlines their investment thesis on going after ultra luxury branded segment with Grivalia Hospitality  - he talked about (in my words from memory not his)

- Greece attractive tourist destination (natural beauty  etc)

- Greece has a shortage of genuine 5 star hotels (even though hotels might call themselves 5 star they are not genuine 5 star hotels by international standards) - a lot of hotels a family owned etc 

- lack of brand name luxury hotels in Greece like Aman, Mandarin etc

- one of reasons you would build rather than buy hotel is that for luxury hotel guests need to have space etc - so existing hotels wouldn't be suitable in most cases

- construction costs have gone up a lot but there is still attractive return even after factoring higher building costs

https://www.youtube.com/watch?v=lRuZ2HXam-A

 

Also I did some digging, according to this website https://theluxurytravelexpert.com/ the Aman Resorts are rated the number 1 luxury hotel brand in the world  (if you are an ordinary person like you me you probably never heard of them! :))

 

 

The Amanzoe Resort owned by Grivalia is run by Aman Resorts & is rated (by same website) the best hotel in Greece

https://theluxurytravelexpert.com/2020/10/12/best-hotels-greece/

& in Europe's top 10 

https://theluxurytravelexpert.com/2021/07/08/top-10-best-beach-resorts-europe/

 

Now with Amanzoe, Grivalia didn't build it, they bought it in 2018  at a total  EV (mostly consisting of debt) of 116M euro.

https://markets.ft.com/data/announce/detail?dockey=1323-13740636-74QQ05NEK6U4F5D19IU8MDVHUB

 

From what I can tell it cost the original owner over 100M euro to build it so it looks like they bought potentially close to its build price.

 

Its unclear what its current EBITDA & valuation would be now & also what GH has spent on the property but given Greece 5 star hotel room prices are up 110% over 2019 to 2022 period, you would think that would be likely positive driver of Amanzoe's valuation & another factor maybe behind GH push in the 5 star space.

 

https://greekreporter.com/2022/06/30/5-star-hotel-rooms-greece-rise/

 

 

 

 

 

Edited May 24, 2023 by glider3834

[glider3834]

17 hours ago, Viking said:

@glider3834 this part got my attention: “When the five planned projects are completed, Grivalia’s value, currently nearly €1 billion, will reach €1.5 billion, says Chryssikos.”

 

I am not sure what exactly Chryssikos is referencing. Fairfax owns 78% of Grivalia Hospitality with a carrying value/market value = $410 million (Dec 31, 2022).
 

The cost to develop and run these properties must be staggeringly high. Grivalia Hospitality will likely bleed significant sums of money until more locations are open and generating significant revenue. Interesting investment. Chryssikos has had the Midas touch for Fairfax when it comes to real estate in Greece. And we know Fairfax loves to bet heavily on winning horses…

 

 

sorry viking I am not sure what they mean by value is that the total build cost/gross asset value before factoring in debt etc?

[glider3834]

https://www.theglobeandmail.com/business/industry-news/energy-and-resources/article-canada-alberta-solar-farm-mytilineos/

 

'One of Greece’s top industrial and power companies is launching a $1.7-billion solar-energy project in Alberta that it says will be the largest of its kind in Canada.'

 

'Mytilineos is backed by Toronto’s Fairfax Financial Holdings Ltd., led by Prem Watsa, which first bought into the Greek company in 2012 and has since increased its ownership to 4.7 per cent, making it the second-biggest shareholder, after Mr. Mytilineos, who owns 27 per cent. Fairfax has an option to take its ownership to 6.4 per cent.'

[nwoodman]

9 hours ago, glider3834 said:

https://www.theglobeandmail.com/business/industry-news/energy-and-resources/article-canada-alberta-solar-farm-mytilineos/

 

'One of Greece’s top industrial and power companies is launching a $1.7-billion solar-energy project in Alberta that it says will be the largest of its kind in Canada.'

 

'Mytilineos is backed by Toronto’s Fairfax Financial Holdings Ltd., led by Prem Watsa, which first bought into the Greek company in 2012 and has since increased its ownership to 4.7 per cent, making it the second-biggest shareholder, after Mr. Mytilineos, who owns 27 per cent. Fairfax has an option to take its ownership to 6.4 per cent.'

 

Thanks for this.  I was just taking another look at the company, MYTIL.AT, impressive. While relatively small position (for now) compared with EUROB.AT.  It has been a cracker for Fairfax.  The market is taking quite a "shine" to Mytilineous, +80% or so over the last 12 months.  I found this recent interview quite informative https://www.strategy-business.com/article/Powering-the-net-zero-transition-at-Greeces-Mytilineos