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100 leading critical infrastructure operators in Australia

Tamtam tracks 314 critical infrastructure operators headquartered in Australia. This list ranks the 100 largest by number of employees on LinkedIn, led by ANZ, Queensland Health and Commonwealth Bank. Their median headcount is 4,024. Half of them were founded in 1920 or later. The most common headquarters are Sydney (22), Melbourne (14) and Brisbane (8).

馃嚘馃嚭 Australia100 companiesUpdated Oct 24, 2026
#CompanyIndustryHeadquarters EmployeesFounded
1
ANZanz.com.au

A banking institution with over 180 years of history, striving to create a sustainable economy for all to thrive and build better lives

Banking 馃嚘馃嚭 Melbourne 50,843 n/a
2
Queensland Healthhealth.qld.gov.au

Largest state healthcare provider offering hospital, emergency, community, mental health, aged care, and public health promotion services across Queensland.

Hospitals and Health Care 馃嚘馃嚭 Brisbane 48,440 n/a
3
Commonwealth Bankcommbank.com.au

Leading provider of financial services in Australia, offering banking, funds management, insurance, investment, and sharebroking products to help individuals manage their finances

Financial Services 馃嚘馃嚭 Sydney 47,706 n/a
4
NABnab.com.au

The company is dedicated to serving customers and supporting communities through their banking services, emphasizing on what matters most

Banking 馃嚘馃嚭 Melbourne 40,896 n/a
5
Telstratelstra.com.au

Providing technology and content solutions for a connected future, with a focus on customer experience and Australia's largest mobile network

Telecommunications 馃嚘馃嚭 Sydney 35,493 1901
6
NSW Healthhealth.nsw.gov.au

Providing comprehensive healthcare services across numerous hospitals with a large workforce dedicated to improving community health and patient care.

Hospitals and Health Care 馃嚘馃嚭 St. Leonards 23,725 n/a
7
Macquarie Groupmacquarie.com

Global financial services organization empowering people to innovate and invest for a better future in 34 markets Visit wwwmacquariecom for more information

Financial Services 馃嚘馃嚭 Sydney 20,757 1969
8
Transport for NSWtransport.nsw.gov.au

A New South Wales government organization leading transport agencies in developing safe, integrated, and efficient road, rail, and maritime networks

Government Administration 馃嚘馃嚭 Multiple locations across the state 18,457 n/a
9
Qantasqantas.com

Global airline dedicated to acknowledging and respecting Indigenous custodians, fostering creativity, diversity, and innovation among its workforce, and prioritizing people in travel

Airlines and Aviation 馃嚘馃嚭 Mascot 18,052 1920
10
Australia Postauspost.com.au

Connecting businesses with consumers through postal, retail, financial, communications, and etailing services focused on continuous improvement.

Consumer Services 馃嚘馃嚭 Melbourne 16,807 1809
11
Westpacwestpac.com.au

A major banking institution in Australia and New Zealand, offering a wide range of financial services globally with a focus on customer prosperity

Banking 馃嚘馃嚭 Sydney 16,224 1817
12
Westpac Groupwestpac.com.au

Leading financial institution offering banking, wealth management, and customer-focused services across Australia, Asia, UK, and the US.

Financial Services 馃嚘馃嚭 Sydney 14,973 n/a
13
QBE Insuranceqbe.com

An international insurer offering commercial, personal, and specialty products in 27 countries to help manage risks and embrace change

Insurance 馃嚘馃嚭 Sydney 14,280 1886
14
Suncorp Groupsuncorpgroup.com.au

Offering insurance, banking, and wealth products in Australia and New Zealand, focused on building sustainable futures, and providing career opportunities and flexibility to employees

Insurance 馃嚘馃嚭 Brisbane 13,529 n/a
15
IAGiag.com.au

Leading general insurance company in Australia and New Zealand, providing coverage under various brands, supporting communities in preventing and recovering from risks since 1851

Insurance 馃嚘馃嚭 Sydney 12,798 n/a
16
Ramsay Health Careramsayhealth.com

Provider of private hospitals, clinics, mental health, diagnostics, and community care services across multiple countries with extensive healthcare staff.

Hospitals and Health Care 馃嚘馃嚭 Sydney 11,896 1964
17
Toll Grouptollgroup.com

Global supply chain and transport services solving logistics challenges for businesses through a network of five hundred sites across twenty-nine distinct markets.

Transportation, Logistics, Supply Chain and Storage 馃嚘馃嚭 Melbourne 11,663 1888
18
AIBaib.ie

Major retail bank in Ireland, providing personal, business, and corporate customers with mortgages, savings, and diverse banking products and services.

Banking 馃嚘馃嚭 Molesworth Street 11,095 n/a
19
Optusoptus.com.au

A leading Australian telecom company offering mobile, internet, entertainment, and business services to over 10 million customers with advanced technology and network coverage

Telecommunications 馃嚘馃嚭 Macquarie Park 11,040 1992
20
Monash Healthmonashhealth.org

A publicly-funded health service in Melbourne's Victoria, Australia, striving for excellence in healthcare, supporting staff, and the community with diverse career opportunities

Hospitals and Health Care 馃嚘馃嚭 Clayton 10,274 1860
21
SA Healthsahealth.sa.gov.au

SA Health is dedicated to improving the health of South Australians through public health services, research, policy development, and quality care with a focus on wellbeing and early intervention

Hospitals and Health Care 馃嚘馃嚭 Adelaide 9,193 n/a
22
Bendigo Bankbendigobank.com.au

Community-focused bank providing trusted financial services and support to millions of Australians, emphasizing customer-centric banking solutions.

Banking 馃嚘馃嚭 Bendigo 8,768 1858
23
Department of Health (WA Health)health.wa.gov.au

Provision of public hospitals, mental health, dental, Aboriginal health, and disaster preparedness services across Western Australia for all communities.

Hospitals and Health Care 馃嚘馃嚭 Perth 6,881 n/a
24
Santos Ltdsantos.com

Global energy company providing reliable, affordable energy; transitioning to lower carbon fuels, including oil, gas, and carbon capture solutions for homes and industries.

Oil and Gas 馃嚘馃嚭 Adelaide 6,628 1954
25
Department of Transport and Main Roadstmr.qld.gov.au

Planning, developing, maintaining Queensland's transport infrastructure and services, ensuring safety, customer service, and sustainable economic growth.

Government Administration 馃嚘馃嚭 Brisbane 6,587 n/a
26
Sydney Trainstransport.nsw.gov.au

A leading transport organization in Sydney operates reliable trains, focusing on customer service, career progression, and maintaining a safe, efficient network

Rail Transportation 馃嚘馃嚭 Sydney 6,549 n/a
27
Origin Energyoriginenergy.com.au

Leading Australian energy company providing electricity, natural gas, solar, and LPG while focusing on affordability, sustainability, and carbon emissions reduction.

Utilities 馃嚘馃嚭 Sydney 6,250 2000
28
AMP Limitedamp.com.au

A retail wealth management and banking business providing financial advice, superannuation, and banking services to help customers achieve their financial goals

Financial Services 馃嚘馃嚭 Sydney 6,100 1849
29
Woodside Energywoodside.com

Operate diversified oil and gas assets globally with focus on safety, efficiency, environmental performance, and growth in gas, oil, and new energy sectors.

Oil and Gas 馃嚘馃嚭 Perth 5,933 1954
30
Virgin Australiavirginaustralia.com

Airline focused on improving flight experiences through new team members, fare restructuring, innovative in-flight services, and sustainability goals.

Airlines and Aviation 馃嚘馃嚭 South Brisbane 5,932 2000
31
The Royal Melbourne Hospitalthermh.org.au

A leading healthcare provider in Melbourne, dedicated to advancing healthcare through research, innovation, and a compassionate workforce, serving the community

Hospitals and Health Care 馃嚘馃嚭 Parkville 5,837 1848
32
Alfred Healthalfredhealth.org.au

Leading metropolitan health service providing specialist medical, surgical, trauma, intensive care, research, education, and training across multiple hospital locations.

Hospitals and Health Care 馃嚘馃嚭 Melbourne 5,721 n/a
33
Western Healthwesternhealth.org.au

A provider of in-hospital and community-based health services in Melbourne's west, working with over 11,000 staff and 700 volunteers

Hospitals and Health Care 馃嚘馃嚭 Footscray 5,626 1953
34
Eastern Healtheasternhealth.org.au

A provider of diverse healthcare services including emergency, surgical, mental health, and community care, with a focus on respect and continuous improvement

Hospitals and Health Care 馃嚘馃嚭 Box Hill 5,548 2000
35
AGLagl.com.au

A leading energy company in Australia, dedicated to transforming how energy is produced, shared, and consumed through sustainability and innovation

Utilities 馃嚘馃嚭 Sydney 5,492 1837
36
nbn庐 Australianbn.com.au

Operates national broadband network enabling providers to deliver fast, reliable, secure internet services across Australia with community engagement.

Telecommunications 馃嚘馃嚭 North Sydney 5,287 2009
37
TPG Telecomtpgtelecom.com.au

A leading telecommunications company in Australia offering mobile, internet, business, and fixed network solutions to consumers, businesses, and wholesale customers

Telecommunications 馃嚘馃嚭 Barangaroo 5,275 n/a
38
UnitingCare Queenslandunitingcareqld.com.au

A prominent health and community services provider in Australia, tackling pressing social issues and reaching people nationwide with courage and creativity

Non-profit Organizations 馃嚘馃嚭 Brisbane 5,208 n/a
39
Ampolampol.com.au

Leading Australian company managing extensive fuel refining, importing, marketing, and retail network serving millions across multiple sectors.

Oil and Gas 馃嚘馃嚭 Alexandria 4,907 n/a
40
St John of God Health Caresjog.org.au

A leading provider of high-quality health care and community services in Australia and New Zealand, focusing on healing, hope, and dignity for all

Hospitals and Health Care 馃嚘馃嚭 Perth 4,826 1895
41
Austin Healthaustin.org.au

A healthcare organization focused on improving patients' lives through specialized medical services, wellness initiatives, and career development opportunities for employees

Hospitals and Health Care 馃嚘馃嚭 Melbourne 4,802 n/a
42
Queensland Railqueenslandrail.com.au

provides safe, reliable, and customer-focused rail transport services across Queensland, supporting communities and integrating with public transport systems

Rail Transportation 馃嚘馃嚭 Brisbane 4,750 1865
43
Water Corporationwatercorporation.com.au

Provides water, wastewater, drainage services, and bulk water for irrigation to homes, businesses, and farms in Western Australia, managing substantial infrastructure.

Utilities 馃嚘馃嚭 Leederville 4,546 n/a
44
Department of Health, Tasmaniahealth.tas.gov.au

The company improves, promotes, protects, and maintains health and wellbeing in Tasmania through high-quality health services and corporate support

Government Administration 馃嚘馃嚭 Hobart 4,488 n/a
45
Qld Healthgov.au

Provides support to parents facing challenges with their child's development and behavior through the Early Intervention Parenting service

Wellness and Fitness Services 馃嚘馃嚭 Waterford 4,294 n/a
46
Insignia Financialinsigniafinancial.com.au

A leading wealth manager in Australia, founded in 1846 to protect families, now offering a range of tailored financial solutions

Financial Services 馃嚘馃嚭 Melbourne 4,262 n/a
47
Healthscopehealthscope.com.au

A leading private healthcare provider in Australia with 41 hospitals, focusing on quality care and positive clinical outcomes for patients

Hospitals and Health Care 馃嚘馃嚭 Melbourne 4,229 1985
48
Department of Transport and Planningvic.gov.au

The integrated Department of Transport plans and operates transport based on the needs of people and products, focusing on destinations over specific modes

Government Administration 馃嚘馃嚭 4,181 n/a
49
Northern Healthnh.org.au

A key provider of public health care in Melbourne's northern region, offering medical, surgical, mental health, and rehabilitation services through four campuses

Hospitals and Health Care 馃嚘馃嚭 Melbourne 4,155 n/a
50
Aurizonaurizon.com.au

Australia's largest rail-based freight operator providing integrated freight and logistics solutions, specializing in transporting commodities and supporting communities nationwide

Transportation, Logistics, Supply Chain and Storage 馃嚘馃嚭 Fortitude Valley 4,024 2010
51
Jetstar Airwaysjetstar.com

An extensive airline group in the Asia Pacific region offering low fares to fly to over 85 destinations with over 5,000 weekly flights

Airlines and Aviation 馃嚘馃嚭 Collingwood 4,003 2004
52
BOQ Groupboq.com.au

A group of challenger brands that provide genuine banking alternatives, focused on building trust with customers, exploring staff potential, and creating social impact in communities

Financial Services 馃嚘馃嚭 Newstead 3,973 1874
53
Sydney Watersydneywater.com.au

Provide drinking, recycled, wastewater, and stormwater services to over four million people across Sydney and surrounding regions.

Utilities 馃嚘馃嚭 Parramatta 3,928 n/a
54
St Vincent's Health Australiasvha.org.au

Leading not-for-profit healthcare provider operating hospitals, aged care facilities, and research institutes focused on compassionate patient care and medical innovation.

Hospitals and Health Care 馃嚘馃嚭 Woolloomooloo 3,904 1857
55
Victoria Policepolice.vic.gov.au

Provides 24/7 policing services across Victoria, supported by diverse professionals, ensuring community safety and effective emergency management.

Law Enforcement 馃嚘馃嚭 Melbourne 3,734 1853
56
Matermater.org.au

A longstanding organization dedicated to improving community health by combining expertise in healthcare, education, and research, with a focus on empowering individuals for better well-being

Hospitals and Health Care 馃嚘馃嚭 Brisbane 3,732 1906
57
NSW Police Forcepolice.nsw.gov.au

A leading police force in New South Wales, Australia, serving a population of seven million across land, sea, and air with community-based policing services

Law Enforcement 馃嚘馃嚭 Sydney 3,694 1862
58
Metro Trains Melbournemetrotrains.com.au

Operator of Melbourne's suburban railway network, running frequent, high-capacity train services across 16 lines to support city growth.

Rail Transportation 馃嚘馃嚭 Melbourne 3,651 2009
59
Barwon Healthbarwonhealth.org.au

Leading provider of advanced healthcare services in Victoria, focusing on state-of-the-art treatment and personalized care for the community

Hospitals and Health Care 馃嚘馃嚭 Geelong 3,588 1998
60
Roads and Maritime Servicesgov.au

A multi-modal transport agency under Transport for NSW, focusing on improving transportation for people and goods through various initiatives and infrastructure improvements

Government Administration 馃嚘馃嚭 North Sydney 3,552 n/a
61
Healius Limitedhealius.com.au

Provides affordable, accessible specialty diagnostic and pathology services across Australia through extensive laboratories and patient collection centers.

Hospitals and Health Care 馃嚘馃嚭 Sydney 3,531 n/a
62
Epworthepworth.org.au

A leading not-for-profit private hospital group in Victoria, offering diagnosis, treatment, and rehabilitation services with a focus on exceptional patient care

Hospitals and Health Care 馃嚘馃嚭 Richmond 3,522 1920
63
Calvary Health Carecalvarycare.org.au

A charitable Catholic health care organization founded in 1885, providing compassionate and quality services to the most vulnerable populations across Australia

Hospitals and Health Care 馃嚘馃嚭 Sydney 3,336 1885
64
St.George Bankstgeorge.com.au

Provides retail and business banking services to over 2.6 million customers with extensive branch network and specialist financial advice.

Banking 馃嚘馃嚭 Sydney 3,327 n/a
65
Cleanaway Waste Managementcleanaway.com.au

Australia's largest public waste management company, operating in over 250 locations Provides waste collection, recycling, resource recovery, industrial services, and workshop waste solutions

Environmental Services 馃嚘馃嚭 Melbourne 3,313 1989
66
Hunter New England Local Health Districtjobs.health.nsw.gov.au

Provides public health services across twenty-seven hospitals, eleven multipurpose centres, and forty-three community health clinics, delivering care to over 920,000 people.

Hospitals and Health Care 馃嚘馃嚭 3,283 n/a
67
City of Gold Coastgoldcoast.qld.gov.au

A vibrant city in Australia, Gold Coast is known for its diverse population, beautiful natural environment, tourism attractions, and rich history

Government Administration 馃嚘馃嚭 Surfers Paradise 3,244 1996
68
The Royal Children's Hospitalrch.org.au

A leading specialist paediatric hospital providing outstanding care, clinical services, trauma center, research, and training programs for children and families

Hospitals and Health Care 馃嚘馃嚭 Parkville 3,244 n/a
69
Bolton Clarkeboltonclarke.com.au

A leading not-for-profit aged care provider in Australia, Bolton Clarke supports over 130,000 individuals with services including home care, retirement living, and residential aged care

Hospitals and Health Care 馃嚘馃嚭 3,239 1885
70
Allianz Australiaallianz.com.au

Provider of personal, commercial, and corporate insurance products including general, workers' compensation, and life insurance in Australia and New Zealand.

Insurance 馃嚘馃嚭 Sydney 3,179 n/a
71
Western Powerwesternpower.com.au

Safe, reliable electricity transmission and distribution across south Western Australia, maintaining extensive network serving over one million customers.

Utilities 馃嚘馃嚭 Perth 3,177 n/a
72
GenesisCaregenesiscare.com

Provider of integrated cancer care globally, focusing on personalized treatment experiences and access to radiotherapy, diagnostics, oncology, surgery, and clinical trials

Hospitals and Health Care 馃嚘馃嚭 Sydney 3,134 n/a
73
Northern Sydney Local Health Districtnslhd.health.nsw.gov.au

Providing acute hospital services and community health care to improve health outcomes for 800,000 residents in northern Sydney.

Hospitals and Health Care 馃嚘馃嚭 St. Leonards 3,041 n/a
74
St Vincent's Hospital Melbournesvhm.org.au

Leading teaching and research health service providing care across Melbourne with a focus on excellence, compassion, integrity, and justice

Hospitals and Health Care 馃嚘馃嚭 Fitzroy 3,007 1893
75
Bankwestbankwest.com.au

Dedicated team at Bankwest focuses on customers' needs Contact via phone or social media for banking services and support

Financial Services 馃嚘馃嚭 Perth 2,949 n/a
76
Opal Healthcareopalhealthcare.com.au

Providing residential aged care services including respite, dementia, palliative, and rehabilitation with 24/7 nursing and home-style hospitality.

Hospitals and Health Care 馃嚘馃嚭 Sydney CBD 2,922 n/a
77
Ambulance Victoriaambulance.vic.gov.au

Providing emergency medical transport, pre-hospital care, and air ambulance services to help maintain life and reduce injuries in Victoria

Hospitals and Health Care 馃嚘馃嚭 Doncaster 2,897 n/a
78
NSW Ambulanceambulance.nsw.gov.au

Provider of high quality out-of-hospital clinical care to over 725 million people in NSW through emergency responses and community safety programs

Hospitals and Health Care 馃嚘馃嚭 Sydney 2,840 1895
79
APA Groupapa.com.au

Ownership and management of a diverse $26 billion energy infrastructure portfolio delivering energy solutions across all Australian states and territories.

Utilities 馃嚘馃嚭 Sydney 2,804 2000
80
Peninsula Healthpeninsulahealth.org.au

A public health service in Frankston and the Mornington Peninsula offering world-class healthcare through hospitals and community services for all ages and specialties

Hospitals and Health Care 馃嚘馃嚭 Frankston 2,756 1941
81
Estia Healthestiahealth.com.au

Provider of compassionate residential aged care with 70+ homes across Australia, delivering exceptional care and enriching experiences for residents.

Hospitals and Health Care 馃嚘馃嚭 Sydney 2,737 2005
82
South Western Sydney Local Health Districtswslhd.health.nsw.gov.au

A large health district in south western Sydney providing patient-focused healthcare services to a diverse population through hospitals and community health centers

Hospitals and Health Care 馃嚘馃嚭 Warwick Farm 2,652 n/a
83
Energy Queenslandenergyq.com.au

Energy Queensland powers communities across Queensland by effectively managing the state's electricity network, minimizing costs, and supporting regional growth and development

Utilities 馃嚘馃嚭 Newstead 2,632 2016
84
Regis Aged Careregis.com.au

A company provides services to older Australians through residential aged care, home care, therapy centers, and retirement villages, with a focus on enhancing wellness and safety

Hospitals and Health Care 馃嚘馃嚭 Camberwell 2,565 1993
85
Spotless Groupdownergroup.com

Provider of various services, now under Downer Group ownership No longer active on social media

Facilities Services 馃嚘馃嚭 Melbourne 2,551 n/a
86
Bank of Queenslandboq.com.au

A regional bank in Australia focused on building genuine relationships with customers through in-person interactions and online engagement with the community

Financial Services 馃嚘馃嚭 Newstead 2,509 n/a
87
Metro North Healthmetronorth.health.qld.gov.au

Public sector health service providing a full range of healthcare services in Queensland, with a focus on best practice, quality improvement, and staff well-being

Hospitals and Health Care 馃嚘馃嚭 Brisbane 2,498 n/a
88
Airservices Australiaairservicesaustralia.com

Air traffic control, aviation rescue, firefighting, telecommunications, and navigation services managing significant Australian airspace and supporting aviation safety.

Airlines and Aviation 馃嚘馃嚭 Canberra 2,488 1995
89
Metro South Healthmetrosouth.health.qld.gov.au

Major public healthcare provider for Brisbane's south side, Logan, Redlands, Scenic Rim, operating hospitals, community, specialty, and statewide services, renowned for teaching and research.

Hospitals and Health Care 馃嚘馃嚭 2,475 n/a
90
Ausgridausgrid.com.au

Australia's largest electricity distributor supplying products and services to 17 million customers, focusing on affordability, reliability, sustainability, and stakeholder engagement

Utilities 馃嚘馃嚭 Haymarket 2,469 1904
91
Veolia | Australia & New Zealandanz.veolia.com

Provider of water and wastewater services, industrial cleaning, waste management, resource recovery, and energy solutions for heavy industry, businesses, and government sectors.

Environmental Services 馃嚘馃嚭 Pyrmont 2,451 1867
92
Fire and Rescue NSWfire.nsw.gov.au

This company is focused on enhancing community safety, managing fire emergencies, responding to various incidents, and running prevention and preparedness programs

Public Safety 馃嚘馃嚭 Greenacre 2,439 1910
93
Queensland Ambulance Serviceambulance.qld.gov.au

The Queensland Ambulance Service provides emergency pre-hospital care, patient transport, aero-medical services, disaster response, and quality First Aid training courses

Hospitals and Health Care 馃嚘馃嚭 Brisbane 2,330 1991
94
Sonic Healthcaresonichealthcare.com

Internationally renowned healthcare provider specializing in pathology, radiology, and primary care with operations in multiple countries and a focus on quality medical diagnostic services

Hospitals and Health Care 馃嚘馃嚭 Sydney 2,328 1987
95
Harbour Energyharbourenergy.com

A leading oil and gas corporation, publicly traded on the London Stock Exchange, specializing in independent operations within the industry

Oil and Gas 馃嚘馃嚭 Victoria 2,324 n/a
96
Qubeqube.com.au

Largest integrated provider of import and export logistics services across Australia, New Zealand, and Southeast Asia with extensive supply chain infrastructure.

Transportation, Logistics, Supply Chain and Storage 馃嚘馃嚭 Sydney 2,301 2011
97
EnergyAustraliaenergyaustralia.com.au

A leading Australian energy company providing practical and sustainable energy solutions, including carbon neutral options, while supporting local communities and indigenous peoples

Utilities 馃嚘馃嚭 Melbourne 2,286 n/a
98
Essential Energyessentialenergy.com.au

Builds, operates, maintains extensive electricity distribution network serving over 900,000 customers across diverse regional and rural communities.

Utilities 馃嚘馃嚭 Port Macquarie 2,263 n/a
99
Australian Red Cross Lifebloodlifeblood.com.au

An organization committed to providing life-giving products and services for the well-being of all Australians through blood donations and clinical excellence

Hospitals and Health Care 馃嚘馃嚭 West Melbourne 2,252 n/a
100
Silverchain Groupsilverchain.org.au

A leading Australian organization providing high-quality, in-home health and aged care services supported by research, technology, and compassionate care

Hospitals and Health Care 馃嚘馃嚭 Perth 2,214 1894

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Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Oct 24, 2026.

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